Call of Duty: WWII

This guide requires you to be familiar with both the Easy Easter Egg (EEE) walkthrough and the process for getting all four of the upgraded tesla guns. DaChiefOfOwnage's written guide
for the EEE is pretty good if you're unfamiliar with it.


Quad Kill has a guide up for obtaining the four upgraded tesla guns.

I have my own written guide for the upgrades kicking around. If people would prefer that, let me know in the comments and I'll add it to this.

These are more or less guidelines for obtaining the Hardcore Easter Egg (HEE). There's a great video guide available on Youtube by MrDalekJD (provided further down) that I used as the premise for making this written guide.

I highly recommend taking time to practice finding the tops and enigma machines scattered about the town area. The locations of these items is randomized each time you play, so getting familiar with all of their spawn locations is key. We found it best to retrieve all tesla upgrade batteries and place them in their chargers as early as possible to save ourselves the hassle in later rounds. This can be done as early as Wave 6 and requires you to have the original tesla gun created.

I also suggest using the following loadouts:
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Loadout A (2-3 people required):
Ability - Frontline
Mods -
Determination*
Specialist Training
Resourceful

Frontline is great because it lures zombies towards you when activated. This comes in handy when needing to defend the levers of the lightning rod or the tesla upgrade stations. Combined with Determination, each time you activate the ability you gain two armor shields which saves you from spending jolts at armor stations.

Loadout B (1-2 people required):
Ability - Camouflage
Mods -
Survivalist*
Specialist Training
Resourceful

Camouflage, here, is used primarily by the person that's solving puzzles, going after tesla gun upgrades, carrying items (batteries), and defending objectives (if needed). Survivalist grants one armor shield when activating camouflage.

*If you don't care about gaining shields by activating your special, you can swap this skill for Pack Rat (Carry a 3rd weapon)
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Video by MrDalekJD



Written Walkthrough
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1. Find all three tops (yellow, green, red) scattered about town and place them in the toy shop window (located next to the Bunker entrance). The location of each of these tops is randomized. They can be found on rooftops, eaves, and window sills.

2. Proceed with the Easy Easter Egg (EEE) and open the bunker door.

3. Find the enigma machines with the red and yellow bows. Each has a number, remember it. The location of each of these enigma machines is randomized. They’re found inside windows around town along with a window in the bunker near the Grease Gun.

4. Spin the top dials via color code so that it matches the number on the enigma machines. These spin in a clockwise direction with each position representing numbers on a clock.

5. Once the red and yellow top dials are set to their appropriate positions, spin the green top until a drawer opens revealing a vinyl record.

6. Pick up the vinyl record.

7. Go to the weathervane near the river and shoot/melee it. Bear in mind, you won’t be able to interact with it until you’ve restored power and opened the bunker door. It’ll spin and then point in the direction of a button (or yellow light).

8. Shoot the button to reveal the conductor (tesla coil) on the water turbine. This will need to be shot later with an upgraded tesla gun.

9. Return to working on the EEE by assembling the tesla gun. You'll end up dealing with a Brenner (Flamethrower zombie). Once you kill it, someone can use it to find the four paintings in the pub, sewer, morgue, and courtyard*. Write down the numbers and their corresponding eagle signs. They'll be needed later.

*You can also shine the Brenner head on the first statue in the courtyard which will reveal a battery for a tesla gun upgrade.

10. Work on getting all of the batteries for the tesla gun upgrades. They'll be needed to continue with the HEE. It's best to obtain all four batteries and place them in their charge stations before attempting to charge them up.

11. Once you have one upgraded tesla gun, go back to the waterwheel and shoot the tesla coil which you had exposed earlier, then proceed to the pub and insert the vinyl record into the record player. This will play some music. Continue with the EEE until the zeppelin has appeared (Left Hand of God).

12. Hit up the switches in the Laboratory and the Morgue that were used earlier for the EEE. There should be a third switch in the Command Center (bunker) that we can activate to reveal a tesla coil. Need a Brenner head available before shooting the coil with a tesla gun.

13. Shoot the tesla coil with an upgraded tesla gun and it’ll open the two grates on either side of the Command Center in the areas leading to the Laboratory and Morgue.

14. Shine the Brenner head on each until you see some numbers appear beneath the object you can interact with. You then need to rotate the dials displaying numbers until they show blue fingerprints. This is timed, so if you miss it you need to wait until the next round to attempt it again.

15. You're rewarded with half of a coin for solving each of the puzzles. Pick up both.

16. Bring the now full coin to the Salt Mines and use it in a panel behind the machine in the middle. It’ll reveal a sword that needs to be picked up. Make sure everyone comes to pickup this sword. Combine with the melee perk.

17. Go to the pub and use the sword to charge up the record player by getting kills. Easiest on a pest round.

18. The record player will change sounds and play a sequence of numbers that sound like knocks or ticks. There will be a long pause before it begins and a short pause between each tick to signify count. We need to remember what those numbers are in sequence. A good trick is to go into Settings and turn off the in game music to really hear the ticks.

19. By this point you need to have the upgrades done for each of the tesla guns. You also need to be at the point in the EEE where you've activated the Voice of God. This is done by using the number sequence gathered earlier from the paintings by matching the number with the appropriate symbol on the center machine in the Salt Mines.

20. Use the number sequence given to you from the record player (the knocks or ticks we listened for in the pub) to enter those numbers into the Voice of God in a clockwise direction, starting from facing the button to activate the Voice of God. Activate the Voice of God a second time.

21. Each person will need to take a turn shooting the chandelier hanging above the hilt in the middle of the room with their upgraded tesla gun. Aim for the candles specifically. If done correctly, each shot will glow cause the chandelier to glow. A prompt will pop up on the screen after you've successfully hit it with each variant.

22. Proceed with shooting the hilt with tesla fire now. Before grabbing the hilt, make sure everyone is loaded up on armor, perks, ammo, upgraded weapons. Jack in the Box help.

23. Retrieve the hilt and proceed to boss fight. This fight is similar to the EEE, but much harder. For starters, only one of the four areas on the zeppelin will open for you to shoot at and it takes much longer to get the batteries off of the zeppelin. You may run out of ammo and need to pickup a weapon from the wall. Go with either the Type 100 or SVT-40.
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If anyone has any feedback, suggestions, or questions, please leave it in the comments. I'm more than open to adding and tweaking things here to make it easier for people to understand. Or if others have some additional information they'd like to provide that they find helpful or useful, please let me know and I can update/add it to the guide.

I wanted to make this guide so you know everything you need to in order to complete the hard version of this easter egg. Doing so will award you with both the Fireworks and Dark Reunion achievements, so if it is your intention to 100% this game I’d advice just beginning with the harder version, so as to do so most efficiently.

Now I won’t sugar coat this, this easter egg is a bit of a nightmare. The sheer number of things you are required to accomplish is quite daunting, and it certainly trumps previous easter eggs in complexity by quite the margin. All I can say is don’t expect to get this on your first try, I will try my best to highlight exactly what is required of you, but honestly the best way to prepare for this easter egg is trying it as many times as you can, so you get as efficient as possible at getting through the steps. My first time getting to the boss fight it was round 29, but when I finally completed it, we got there at something like round 17 or 18 (needless to say the lower your round, the easier).

Prerequisites

Now, there is nothing the game requires you have done previously to complete this, that being said, there are many things you can do to greatly aid yourself.

Know the map

Before you even start this, understand everything about how the Final Reich works. If you've played zombies before, you will notice many similarities and many differences, particularly in how juggernog now works, being replaced with armor. Know how to unlock pac-a-punch, know where each door leads, know the mystery box locations, know the different enemy types and how to deal with them, know escape routes, know the perk locations, and their functions, know how to share points, and how to maximize points, know how to use consumables and self revives, etc. If you have a thorough understanding of this map it will be much easier to navigate through this easter egg.

Find a solid team

This can be done with as few people as you want, but obviously the more the merrier, doing it solo naturally makes it significantly more difficult. That being said, it is important everyone in your game be very familiar with the map and the easter egg steps, I'd suggest you find a group who hasn't attempted the easter egg yet and learn it together. If even one person isn't totally sure about what they're doing, it can make everything quite challenging. It is also important you communicate well, a key aspect of this easter egg is keeping zombies alive at the end of rounds and killing specific numbers of specific zombie types with specific traps, so it is paramount you are communicating well.

Have the right loadouts

Making sure you have the proper loadouts is very important for completing this. In terms fo starting weapons, I'd suggest everyone equip the 1911, because it can be upgraded to the extremely powerful bacon and eggs, similar to the mustang and sally from black ops. This can save your butt if you get cornered because of its high explosive damage, and it also does not damage the player. This is also an excellent weapon to use against the blimp, which is pretty important during the boss fight.

In terms of abilities, it is important 1, and really only 1, person have frontline, which attracts all zombies to that player for a short time, making defending batteries and the lightning rod much easier (and you do a ton of this). Make sure this player also equips the mod determination, which gives them 2 armor points with each activation.

The other players in the game should really all be using Shellshock but only if they also equip the mod sustain zone. This means every time a player activates their ability, a lingering forcefield spawns at their position which freezes any zombies that enter it. Doing this gives you and your team mates about 30 seconds of invulnerability where they can shoot the hell out of zombies (as long as they stay in the sustain zone). You can also equip this with the mod protector which gives all your team mates (but not yourself) a point of armor when they are hit by the shellshock.

It should be noted that shellshock does not stop the main boss, so it is probably worth having one player run camouflage so in an emergency they can become completely invulnerable for a short time and revive downed team mates.

In terms of other mods, it is largely up to you. You will see some mods are much better than others. It is very important you have a mod that allows you to get armor without buying it, besides that it is usually helpful to run "specialist training" to charge your meter faster.
It should be noted that all the mods do not unlock by default, you need to spend raven research tokens, which you get one of every time you level up, to buy them. As such, it can be more difficult to complete this low level, until you get access to some more useful mods (sustain especially can take a long time to unlock).

In terms of consumables (which you only get from supply drops, how fun). Its usually a good idea to run max ammos and full specialist meters, during the boss fight you get a max ammo after every stage you complete, but if you are not conservative with ammo it is easy to quickly run out making it quite difficult, hence the max ammo consumables.

If you think you're ready, and you got a squad together, start a custom game on The final reich.

Now for this guide, I will assume you know the general map layout. I won't go over pac-a-punch but its very easy anyway, some of these steps are part of the fireworks easter egg, and some are for the hard core, you need to everything I specify here to complete the hard easter egg (including building all 4 tesla gun variants). I'm going to try my best to lay out the order you should everything in, but understand there are effectively 3 separate easter eggs going on here: The fireworks easter egg, the additional steps for the hardcore easter egg, and building all 4 tesla guns, these three can be done in any order for the most part, but it is important you minimize the round advancing as best you can.

Step 1: Shooting some tops

The first step is quite easy thankfully and can be completed very early. There are three spinning tops hidden around the top town area of the map, being coloured red, green and yellow. Their locations change every game. The tops are fairly large and colourful so they are easy to spot. Rather than list out all the possible locations check out this video, I take no credit for it, all credit goes to GregFPS on YouTube:


Shooting the tops will cause them to fall down and you can pick them up. You may have to open some doors to access the tops, remember you can share a minimum of 250 points to other players to allow you to open doors without ending the rounds. Once you have shot all 3, you can head up to a toy shop window ride beside the large bunker door, where you can place all three. You will see that by holding on one of the tops you can rotate it clockwise slowly. You should also notice an arrow on each top. You can imagine each top as a clock, and the arrow being the hour hand, and you need to set each of the 3 clocks to a specific "time" (1:00-12:00). But what time do you set them to?

You need to find these peculiar looking type writer like devices that are hidden outside of the map, their locations change every game as well, the same video above shows the locations of each enigma machine.

If you look at an enigma machine you will see it has either a red, yellow, or green bow on it, obviously correlating to the spinning tops. You will also see it is showing a particular number between 1 and 12. It can be difficult to see the number sometimes, but just remember that the number is never 3 digits, so you only you have to see the 2 right most digits. You then want to set the corresponding top to that specific number as if it were a time. So if you saw a 7 on the enigma machine with a yellow bow, you would set the green top so the arrow is pointing to the 7 o'clock position, super simple stuff. Now, simple logic would suggest you only need to find two enigma machines, as once 2 tops are set, you can quickly cycle through the third top's 12 positions until you complete it. When all tops are set correctly a drawer will open with a record inside, which you can grab. You won't need this for quite a while.

Step 2: Open the salt mine doors, Hal

Now doing this is actually quite easy and you probably accidentally did it without actually going for the easter egg. Once the bunker is open. You need to open both the morgue and laboratory doors, again, make sure you are maximizing those points. Once you have enough to open both doors, try not to kill any more zombies. Inside both areas there is a power switch which both must be hit within a few seconds of eachother to power the salt mines. Right in front of the salt mine door is a pyramid like device which you can open.

Step 3: Hurricane battery You now want to get enough to open the salt mines, but, when you do, be careful. About 4 or 5 explody dude zombies will be present in the salt mines, do not kill these guys just yet! You want to keep your distance and lead one of them to the laboratory. Bear left all the way in here until you reach a set of stairs, about half way up these stairs is a large electrical panel on the wall. You want to be standing right beside this and have the explody dude explode right beside you. This will open up the panel revealing a large battery, grab this battery and run it to the large electric trap in the center of this room, where you can place it in an obvious holder right in the center. There's nothing you can really do with that this early in the game though.

Step 4: Charge the emperor's hilt

Head down to the bottom of the salt mines and activate the large machine called the emperor's hilt. Doing do will cast a red circle around you. You need to kill about 20 zombies within this circle to charge the hilt. Zombies that do charge the hilt have a very obvious red electricity effect present when killed. When you have killed enough an obvious red glow will occur, and you can run back up to the top.

Step 5: Gather the Tesla gun pieces, and also build it

In the main bunker area, if you run up the stairs you will be able to interact with a control panel that faces the salt mine doors. Doing so will cause the map to go quite dark, and the machine you just filled with souls will be present hanging from the ceiling in front of the salt mine doors. You will see that there is a red circle around on the ground. Same idea here, kill zombies in that red circle, but ooooo, this time the circle moves, crazy! The machine will follow a track on the ceiling towards the laboratory. Follow it and keep killing zombies beneath it in the red circle. If you don't kill zombies it will stop moving until more are killed.

When it eventually reaches its destination at the end of the laboratory, it will go through this sequence for a few seconds, try to hold on to any zombies at this point to keep the rounds low, you will need their souls in a few seconds. The machine interacts with another machine and will eventually produce a part for the tesla gun, grab it.

The device will now slowly follow the same track back to where it started, no need to kill zombies this time.

When it finally reaches the main area, its the same idea, kill zombies beneath it and power it along the track towards the morgue. It will retrieve a piece eventually, quite simple stuff.

Now, that second tesla gun piece you might not want to grab just yet, because when you do the huge flamethrower zombie will spawn as soon as someone enters the main bunker area. This guy is more annoying then anything, he doesn't do a ton of damage, and as long as you keep your distance he's hardly a threat. His weak point is the tanks on his back, so I'd suggest you have gotten some decent weaponry from the box at this point to take him out easily.

Now pay attention to where you kill him, because you will need his head in a second.

If you now head up to the circular table like thing by where you activated the device in the bunker you can craft the tesla guns (all tesla gun variants are crafted here also). The base tesla gun is decently powerful at lower rounds, and you will need it for a number of steps coming up, all players should grab one.


Step 6: Activate the right hand of God (it's on the left)

Head down to the emperor's chambers and activate the right hand of God, a large literal hand on your left as you enter. Now head up to the bunker, and on the wall opposite where you built the tesla gun, you will see a panel. Activate this and it will show you 4 lights (each either red, green, or blue) labeled 1-4. You need to remember the order of these lights, and communicate it to your team. You need to now quickly run to 4 different power stations around the map and switch them to the appropriate colours. So say the order of the colours on the first thing was red, blue, blue, green. The first panel would be switched to red, second blue, third blue, fourth green, quite simple. Thankfully the locations of the panels doesn't ever change, but, a panel can not be activated until the previous panel in the sequence is changed the right colour.

-Panel 1: Very obvious, directly to the right of the initial panel giving you the colours.
-Panel 2: Dropping down the big hole in the town, head towards pac-a-punch and you will see it on the intersection leading to PaP and the morgue.
-Panel 3: Leaving PaP and heading towards the docks, it is on your right just before the door.
-Panel 4: Exiting the top floor of the pub it is on a wall to the right of the door leading to the lightning rod area.

The more people in the game the less time you have to hit all 4, as such, it is easiest if you have someone waiting at each panel, you do still have quite a bit of time so there is plenty of room for not being super fast. You set each panel to its necessary colour by holding on it until the correct colour shows, very easy.

Step 7: Defend those lightning rods

Have all players come to the lightning rod area, activate the central machine in the area and a health bar will appear above it. Zombies will start rapidly spawning and attacking the machine, you just need to defend it by killing these zombies. This really is quite easy, the machine can take quite a bit of hits before it dies, I literally have never failed this step. If things look scary, don't be afraid to activate some abilities, one person activating shellshock with sustain zone can incapacitate every zombie around you for a long time, or the guy using forntline can activate it and run the zombies far away.

After about 90 seconds, you will have passed this, and need to do the exact same thing again, but now defending 2 machines on opposite sides of the area. Activate both machines at the central machine's 5 and 7 o'clock (when your back is to the rest of the map), and do the same thing, just be weary there are 2 machines now.

Once you have done this a few times it becomes basically child's play, considering you will likely be on a very early round at this point. What's annoying is the rounds advance while you do this, so you really have no choice but to go a few rounds during this step.

You can go interact with the right hand of God again to complete this step.

From this point, you are free to begin upgrading to the 4 Tesla gun variants, now unfortunately, doing this requires you kill specific enemy types with certain traps around the map, which can be incredibly annoying, they can be done in any order really, the issue is just getting the proper enemies to spawn.

Step 8: Midnight battery

Remember the Brenner head you got from killing the flame guy, go find it. Now you need to head to the courtyard area (by the bouncing Betty trap). There is a small statue of a Sheppard to your left as soon as you enter the area actually hit by the bouncing Betty trap. You can shine the Brenner head on this statue with to make it crumple, revealing a battery inside. Shoot the battery with a tesla gun to make it pop out, grab it, and place it in the holder directly to your right.

Step 9: Charging the midnight battery (regular zombies)

Charging this battery is probably the easiest of the bunch, because it just requires normal zombie kills. You need to kill zombies using the bouncing betty trap to charge the battery. However, it only counts as a charge if you kill a minimum number of zombies with a single activation of the trap. You need nearly an entire group of zombies to be killed by one activation of the trap for it to count as a single charge. As such, you need your entire squad to train up zombies near the bouncing betty trap and run the zombies through, acitvating it and hopefully killing enough.
Something of note, you can tell before activating the trap if there are enough zombies by looking at the battery. If there is a suitable number in the vicinity a green light will turn on. The betties damage you as well so be careful. You will know you got a charge into the battery if there is a distinct flash of electricity coming from the battery, meaning you got enough. Now, you need 2 charges to fill this (and all batteries) up, meaning you need to activate the bouncing betty trap on 2 full groups of zombies, it is impossible as far as I know to do it in one activation. This can be quite difficult at first because the area is quite tight and you need to coral all the zombies into a specific area, it takes quite a bit of practice to get it done efficiently.

Step 10: Defending the midnight battery

Once you have given the battery 2 charges, you will be given the option to pick it up (if no option exists, you will need to get another charge). While holding the battery you move very slow, so be careful. Go down the ramp into the laboratory, and you need to place the battery to the left of the machine that gave you the tesla gun part, in a little opening. Now activate the battery and, just like the lightning rod step, you need to defend it from zombies for around 60-90 seconds. This is not super difficult, and if need be you can acitvate the electric trap right in front of you that attracts all zombies and kills them. After defending, the machine plays an animation and after a bit you can grab a piece from the same place you got the tesla gun piece.

And with that the midnight tesla gun is complete, you build it in the same place you built the first tesla gun, but only one player can have one at a time.

Each tesla gun variant follows these same general steps:
1.Miscellaneous task to retrieve the battery
2. Charging the battery by killing a certain number of a specific enemy type with a specific trap in 2 activations.
3. Defending the battery

Step 11: Retrieving the bloodthirst battery

Doing this takes a bit of practice and memorization, but it is not that difficult. Head to right beside the statue you got the previous battery from, if you look to the left of this area, you will see a street light subtly flickering, it can be kind of hard to distinguish.

You need to shoot this flickering light with a normal tesla gun, doing so triggers a loud and obvious noise. If you look to the left of this light another light up the road a bit will begin flickering, you need to shoot this one, and all subsequent ones, with any bullet weapon, again, the loud noise indicates you hit it. After you hit a lamp, another one starts flickering and so on. You want to carefully follow this trail shooting every lamp until you get to the morgue, where shooting the final light will trigger the battery to spawn in the center of the spike trap room. If you get lost and can't seem to find the next light in sequence to shoot, use a video guide to see the path, it may be much easier for you.

Pick up the battery and place in the battery holder beside the spike trap activation.

Step 12: Charging the bloodthirst battery

Charging this guy up is pretty annoying, because it requires you kill pest zombies. Pest zombie rounds happen every 5 rounds, so you can do quite a bit of waiting to get this done. As with the first battery, you need to kill 2 full groups of pests with 2 activations of the spike trap to charge this, which means you need basically a minimum of 2 pest rounds to complete this, you see why this easter egg is so annoying now? You will want to have all players train the pests in the spike trap area and try and kill a full group of them, again check for that green light and electricity. You can also stand on the spike trap to bait the pests, and it does not do a whole lot of damage to you.

Step 13: Defending the bloodthirst battery

Exactly the same as the previous battery, once it has 2 charges, grab it and run it up near the entrance to the morgue, place it in the opening to the left of where you grabbed the second tesla gun piece, activate it and defend it, nothing special. Once done, same as before, grab the piece and build the bloodthirst where you built the other tesla guns.

Step 14: Retrieving the reaper battery

This is fairly easy, it does however require a single wustling. If you head into the PaP area, coming from the morgue, on your right immediately as you enter there is a locker/ electrical type panel that looks exactly the same as the one for the hurricane battery. The difference here is you need a wustling zombie to charge the panel. Simply lead one near it (preferably without any additional zombies), shoot it, and have it charge you with your back touching the panel, just stand still and take the hit, and the battery will be revealed, same as before, place it in the holder a bit to your right.

Step 15: charging the reaper battery

This is arguably the most difficult battery to charge, and I find it can also be a bit finicky. You simply need to kill 2 groups of 2 bomb zombies using the saw trap in pac-a-punch. The issue with bomb zombies is, although they do spawn somewhat frequently past about round 8 or 9, if you get anywhere near them they explode and kill themselves, so you obviously need to avoid doing this. The best strategy is to shoot the bomb off the back of the bomb guys, you do this by shooting the little guy on his back holding the bomb in the head, careful though because hitting the bomb detonates it. With a bit of practice this can be a pretty easy shot to make, since the bomb guys move pretty slowly.
You also need to make sure you keep track of the bombless guys in your horde of zombies and try and save at least 2 of them for the end of the round, this is why having competent team mates is so important, because they may shoot the bomb zombies which can make this very difficult. Lead the 2 bomb zombies into the pap area and, just as before, activate the saw trap and kill them, and just as before, you need to do this all twice, fun. I found on this battery in particular it didn't always work, because I would clearly kill 2 but it wouldn't register a charge, so just make sure the green light on the battery is on.

Step 16: defending the reaper battery

Nothing special, take it to the same spot in the morgue that you did the bloodthirst battery but on the opposite side. I should also mention that you can't place and defend more than 1 battery per round, so if you can't seem to place a battery that's likely the reason.

Step 17: charging the hurricane battery

Remember the hurricane battery I mentioned earlier? The one that required an explody dude explode near the locker, yeah that one. Again, you want to make sure you retrieve that battery with the salt mine bomb guys, since the reaper battery is so demanding of bomb boys you can't really spare any later on.
Once the bomb is placed in the electric trap holder, you simply need to kill 2 groups of 2 wustling with the trap, which is easier than you think. For one, wustling don't count as zombies to advance rounds, so you can save them across multiple rounds, and they don't really pose much of a threat because of their slow speed. So simply don't kill wustling until you have 2 alive, walk them into the trap and activate it. This trap attracts all zombies to it anyway for some reason, so you don't even need to have the wustling be in the tunnel when you activate it, just near it. As always you need to do it twice with 2 wustling in each go.

Step 18: defending the hurricane battery

Super simple, just as before, opposite where the midnight battery was placed.

Now, you need to make all 4 tesla gun variants to complete this easter egg, but only one player can have one at a time, they are quite powerful and really help you in a pinch. Although I listed the steps for these tesla guns using steps, they can and should all be built at the same time. Understandably a significant portion of building these requires you get the right enemies to spawn, which is where the major challenge and need for high coordination comes in for this easter egg, so know what enemies you need at all times and make sure you have retrieved and placed as many batteries as you can as early as you can. Things like making sure you know the pest round is next (remember it happens on rounds 5,10,15,20... etc.) so everyone can be in the morgue spike trap area to start, or calling out bomb zombies and their locations so your team doesn't accidentally kill them.

Step 19: Shooting the zeppelin

Back on track with the actual easter egg steps, again, these steps should be done while you are upgrading the tesla guns, not after. You now need to activate the left hand of God in the salt mines, opposite the right hand of God (obviously). Doing so spawns a giant zeppelin boi in the sky over the town area of the map. It is advised you don't activate this until you are ready to complete the step, as the zeppelin will shoot down at the map and can damage you and kill saved zombies. It is easiest to have one person holding a few zombies out of harms way in the bunker, while the other three shoot the zeppelin. You will see it periodically open these 4 panels around its body, exposing green glowing lights. Shooting these make them turn colour as they take damage (green- yellow-red). Now, easily the most effective gun to use here is the bacon and eggs (upgraded 1911), as it will very quickly damage the zeppelin. The issue is, the bacon and eggs has very little ammo, and there's really no need to waste it here since you can take as much time as you need. As such, I'd suggest you use some LMG or assault rifle (upgraded preferably but its not super necessary). Once one of the lights is red, once it receives enough damage it will drop a large generator type thing somewhere in the town area. Look where it dropped and run to it.

Step 20: Charging the generator

Very simple, because this zombies mode is extremely creative, you need to kill zombies near this generator that dropped so it can harvest its souls or whatever. After maybe 20 or so kills, it explodes and leaves a battery identical to the ones used to upgrade the tesla gun. One player need to grab this battery and slowly hobble along down to the left hand of God and place the battery in one of 3 holders. Since you are very vulnerable carying the thing you should either have someone protect you, or wait until the end of a round. I've heard that if you leave the battery for too long it is sucked back in to the zeppelin but I've never seen it happen so...

Step 20: Do it all 3 more times kind of

So once you place that first battery, you just need to do the exact same thing you just did to get 2 more batteries, nothing changes. There is one small change though. The zeppelin is a cheeky little prankster so on the third generator it drops, as soon as you get near it, the generator gets sucked back in to the zeppelin (PRANK'D!!!), but that doesn't matter, just shoot the zeppelin again to get a new one. This whole zeppelin part is super easy if you have someone holding a zombies, the zeppelin does shoot you but it won't ever damage you enough to take armor, very simple step, activate the left hand of god with all 3 batteries placed.

Step 21: Look at some birds

Find that pesky Brenner head. Now you need to shine it on 4 painting around the map. Each painting will reveal a raven in a specific formation, and a roman numeral, the paintings are located:
1. In the pub, right next to the bar.
2.In the morgue, next to the spike trap
3. Sewers, next to pap
4. In the courtyard, near the bouncing betty trap.

Now either write it down or memorize it, or just have someone already in the salt mines. If you look in the center of the God room, you will see a third contraption called the "voice of God". If you look around this thing, you will see the same raven symbols and a mechanism that cycles through different numbers for each of the 4 symbols. Now, if you're a genius, you've probably assumed that you simply match the raven symbol in the tone of God to the roman numeral that is on its painting, and you're right. Very simple stuff, the raven symbols can be difficult to communicate to one another because they look sort of similar, but I'm sure you'll manage if you got this far.
If all 4 numbers are correct, activate the tone of God and boom boom. At this point you are ready for the fireworks casual easter egg boss (for that one you don't even need to upgrade the tesla guns, its kind of laughably easy). But I'm sure you're here for the hardcore easter egg because you're super hard core, for that, there's a few more steps.

Step 22: Shoot a yellow button

Now, head to the river area and you will see a very obvious weather vane sitting on the wall facing the river (again, this can be done as soon as you have that vinyl record from earlier). Melee this weather vane and it will point in some direction. It is pointing in the direction of a very small yellow button Try and follow where it is pointing and look for the yellow button on the wall somewhere. This thing can be quite difficult to see, so you may want to look at a video.
Shoot the yellow button with any bullet weapon.

Step 23: Shoot the water wheel

Now right below you on the docks you will see a water wheel. On it is a tesla coil looking thing. You need to shoot this tesla coil looking thing with any upgraded tesla gun.
After doing this, you can head into the pub and you will see a record player on the bar. You can place the vinyl record you got earlier on this record player, more on this in a second.

Step 24: Turn on the power, again?

Yeah, so the two switches you activated to turn on power to the salt mine deactivate at this point for no reason, go ahead and flip them both on. Now you need to quickly run to in front of the salt mine doors and to the right you will see a third power switch be revealed, which you must also switch on (you are timed in doing all this, so have 1 person at the morgue switch and 1 at the lab switch to start).

Step 25: Shine a light and turn some dials

Now, to activate this next step, you need to shoot a tesla coil looking thing underneath the 3rd power switch with an upgraded tesla gun, but don't do it until you're ready, because you are timed and can only do this once per round. Make sure you have placed the brenner head right at your feet so you can grab it as soon as you shoot, now i would suggest you actually have 2 people with a brenner head here (you will likely have killed 2 brenners by now), one person goes lab side, one goes morgue side. Basically, once the tesla gun is shot, run through either the morgue or lab door, and immediately on your left is a now opened grate with a series of numbers you can cycle through. Shine your head on this and it will reveal a number, ignore that number completely. You just need to cycle through each of the 5 number slots until they show a number that glows slightly blue, that's it. Now, of course, you need to do this on both sides. Now, I am fairly sure that as soon as you shine the brenner head on the grater, it will remain open permanently, so if you only have on person doing both "puzzles", I would suggest they shine the brenner head on one, then quickly run to the opposite side and shine it on the other.
If you don't shine a light on one it will eventually close, and you need to wait a round to try again.
Inputting the correct 5 digit code will give you 2 1/2s of a coin (1 coin half from each side).
Now, bring these two coin halves down to the God room, and at the very back of the room, there is a spot you can place them. Doing so lets you grab a very powerful sword weapon, which all players should grab.

Step 26: Charge up the record player

Now, this part you would think would be quite difficult, but every time I've tried it its been pretty easy. The sword is a very powerful weapon, if you're on a high enough round to where it is no longer a one hit kill, buy the melee perk. For this step, you simply need to kill a bunch of zombies in the pub with the sword, that's it. Now, the pub is a tight space, as such I suggest you put 2 people in the pub, and 2 people somewhat near it, who simply train up zombies, and kill the slowly.
Now, as I understand if the people swording the zombies leave the pub area, the counter resets, so, don;t do that I guess. As I said the sword is very powerful, and you can quite literally sit in a corner by the record player and swing away and you should be fine. If you are really paranoid, doing this on a pest round is much easier, but either way you should be fine.

Step 27: Listen to them ticks

Now, once the record player is sufficiently charged you should start hearing it making these distinct ticking noises. It is playing a repeated series of 4 numbers, each number being represented by however many ticks (3 ticks= the number 3, etc.). So you need to listen very carefully to this record player, jack up your game volume and tell everyone to shut up for 10 seconds. The sequence repeats after a sizable pause, and each number is separated by a smaller pause. So listen for the long pause and count how many ticks are between each small pause. You will end up with 4 numbers in a specific order, remember them obviously. I'd suggest a few people listen to the record player to make sure you have the right numbers. It can be quite difficult to distinguish the ticks, because the record player also plays spooky pitch shifted old timey music, so listen carefully.

Now remember the voice of God? Head back to that thing. Now, facing the button to activate the voice of God, you want to enter the numbers in a clockwise direction, meaning the first number is put in the thing to your left, etc. When all the numbers are inputted right activate the voice of God for a second time.

Step 28: Shoot the chandelier

Now is the part where all 4 tesla guns are required. In the God room, there is a very obvious chandelier thing above your head. You simply need to shoot this once with all 4 tesla guns, it doesn't need to be same player who shoots it. You will want to aim for the candles on the perimeter of the chandelier, and you will know you hit it if the circle fills with coloured electricity, super simple (assuming you have all 4 tesla guns of course).

Step 29: Murder death boss fight

So now is the boss fight. Now, at first glance this boss fight can seem incredibly daunting, because it is much more complicated than simply shooting the bad guy over and over. But honestly, it is not that difficult. The actual boss is quite slow and easy to avoid (but he does a ton of damage so do avoid him). And the zombie spawn rates are fairly manageable. With 4 people, as long as you are patient enough, this can be done worry free.

Now, obviously, you want to be well geared up for this thing. Have full perks and full armor, plus a bacon and eggs, an upgraded tesla gun, and an upgraded LMG or assault rifle (if you're running pack mule). At least one person should also have Jack in box. Considering the insane amount of time it takes to get here, its probably not in your best interest to fail during this. So play smart and be safe, don't go for overly risky revives, if someone bleeds out they can come back if you manage to advance the round.

When you're ready, have all players head to the God room, and shoot the hilt with their tesla guns at the same time, now hold x on the hilt to activate a cutscene. You will see a grotesque and honestly quite terrifying body horror monster emerge from the river, and will spawn right in front of it (naturally get the hell out of there).

Now during this fight, you are restricted to just the town area of the map, and the boss will constantly pursue you at a slow pace. As such you should be constantly circling the whole playable area as a group, keeping as much space between you and the boss as possible. If he lands a single hit on you even at full health it takes a point of armor or downs you (if you have no armor). So how do you beat him?

Well, you will notice that the pesky zeppelin from earlier is back. However, because this is the hardcore easter egg, it only opens one of its 4 slots at a time, so it is much harder to actually land damage. It is here that the bacon and eggs are super useful. Just as with the first zeppelin step, you need to get it to drop a generator, which means eating away at 1 of the 4 spots until it does. Since there is such a brief window of attack, using the bacon and eggs is usually smart, if you are coordinated you can even get a generator in a single cycle. Of course, the giant demon monster and the zombies do not make this any easier, so coordinating damage on the same target is very hard. First and foremost worry about your own safety, if you are a decent distance from any enemies, then you can go ahead and keep an eye on the zeppelin and try and damage it a bit. It never heals itself, so any damage is good damage. Once enough damage is dealt to a single target, just as before, it will drop a generator. As well, just as before, you need to charge it up by killing zombies near it. Again, be cautious, don't stick around the generator and let the boss get in your face, circle around and only kill when he's far away.

Once you get enough zombies, as you would expect a battery drops. Now, I would advice you first move this battery so it is in a prime location. I would suggest the central area of the map since it is wide open. Basically, your job is to shoot the boss until he gets stunned, and place the battery on his leg, now that's all easier said than done. It doesn't take a crazy amount of damage to take him down, but the challenge is timing everything. One of the fun modifications the harder easter egg gives us is a significantly reduced stun time on him. Because of this, you have basically stun him, and immediately place the battery, you have maybe a 1 to 2 second window. Now, what's annoying is the boss will frequently kneel when you damage him enough, but won't be stunned, he is only stunned when the text on screen says he is stunned, and it is only during this time that you can attach the battery. I would suggest you have one guy just sitting right beside the boss holding the battery while the other unload on him, so he can immediately place the battery when he is stunned. The area you can place the battery is kind of specific as well, so often times you will be right beside him holding x trying to place it but to no avail. If he does get stunned and you miss the battery, don't worry, that's kind of to be expected, just start shooting him again, you don't need a new battery or anything.

Once you do finally hit him with the battery the first time he will run away for a few seconds (and drop a max ammo, which you should obviously grab) Typically a flame zombie and a bunch of wustlings will spawn here, take them out, not too difficult.

Eventually the boss and the zeppelin will return, and, you guessed it, just do it all again. Shoot the zeppelin, drop the generator, kill zombies near it, stun the boss and place the battery, exactly the same as the first time. What's nice (if you can call it that), is the fight doesn't seem to get any harder, the boss doesn't get faster or start shooting missiles or something (as you would expect), it is just doing the same thing a few times, so as long as you are patient and not too risky, you will be fine.

Now, as I'm sure you may have guessed, after the 2nd battery is placed, you must shoot a 3rd generator. Oh, but that nasty zeppelin is still a little trickster so he yanks that 3rd one back up just like last time so you have to waste more time and ammo, yay. On the fourth generator it is business as usual, exactly the same as the first 2. When the third battery is finally placed, it's done. You get a cutscene and both the fireworks and dark reunion achievements, congratulations. Now go outside.

Conclusion

This easter egg is quite a nightmare and a huge challenge for even veteran zombies players. I hope this guide gave you everything you need to know and enough tips to get it done, as I said, having a committed and competent crew makes this much easier, as coordination is paramount. On your first few attempts this may seem borderline impossible, but I assure you the more you try it the easier it gets, once you know the steps and how to upgrade each telsa gun you can breeze through everything quite fast. The boss fight can throw you for a loop if you are not careful, but just be patient and you'll get it done.

If you have any tips on how to improve the guide or make this easier please feel free to let me know in the comments or message me directly. As well, if you are confused about any steps let me know and I'll try and help you out as best I can. Good luck!

Videos if you prefer those
(Note I take no credit for any of these, YouTube channel above each respective video.)

Fireworks easter egg (easy easter egg, all these steps are still required), MrDalekJD


Hardcore easter egg (any additional steps that aren't part of the easy easter egg), MrDalekJD


Upgrading all 4 tesla guns, GregFPS