Xeno Crisis

First off access the cheat menu by highlighting options and holding LT+Y+left+start. This allows you to turn on infinite ammo/grenades as well as using stage select to retry the level as much as needed. Also, access the backer menu by holding LT+Y+right+start and choose backer 7. This allows you to progress to the boss fight while still using cheats as otherwise you'll receive an instant game over upon reaching him.

Tip from Bastian Reader is to do 2 player mode as the ranks are separate and the extra player can help to distract some of the enemies off you. And obviously if you have an extra person to play local co-op these will potentially be much easier. Although I'm fairly certain the bosses have double the health while playing co-op so it may not be worth it for the trickier bosses without an active 2nd player.

Basic strategy for all levels is spam grenades with LT while trying to keep your back to a wall without a door on it as there is virtually zero spawn protection with enemies popping up or jumping right on you if you're anywhere off the wall.

Again S rank has nothing to do with score so don't even bother going for extra grenades/health/rescuing hostages if it remotely puts you in danger. I typically would go right for the hostages if possible just to clear them off the screen and have one less distraction but if they're right next to a spawn door then I wouldn't bother.

This level took me the longest of them all to S rank. Didn't find any particular seed that seemed any better than the others. Always go up when available as the side rooms generally just have extra hostages and are not required for S rank. Try to prioritize the bigger turrets. The shielded enemies can have their shields broken with a roll using RT but I always stuck to grenades for them to keep distance.

You can see in the clip I get hit once and nearly muck it up on the room before the boss. Thankfully this boss is fairly easy with grenade spam. Just focus on clearing the spiders out and try to make sure they don't drop right on you. For the 2nd phase I found that sitting in the bottom right corner he couldn't hit me with his bullets and my grenades still reached him so it's just a matter of fanning your analog stick to clear out the spiders. It definitely looks a bit iffy at times but feel free to practice it in boss rush. I used this strategy 3 times in a row with no hits taken.

Good luck and if you're having a lot of trouble it might be worth trying a different seed in the cheat menu to see if you fare better on a different layout but it really all comes down to practice and a slight bit of rng with the weapons. I personally found the BFG to be the worst weapon as it's far too slow and has some kickback resulting in me getting hit nearly time I used it. But the rocket launcher/laser can help quite a bit in making short work of a tricky room.

Game is still a very easy 750gs with the cheat menu but if you want the completion you're still going to have to work for it with these S ranks.

Getting an S Rank means that you can only get hit 0 of 1 time during the entire level.

Getting to the boss for this level can be a bit tricky, but I found a way to reduce the number of enemies that you individually need to kill to make it a lot easier to get an S rank on the last level. All you will need are two controllers. If you want the same map layout as me use Seed 53,215 (yes that is a high number but it was a random seed for me and I managed to get it my first try).

Here is my full run using two controllers. Remember to use the debug and backer menus.


First of all, you will want to bring up the debug menu. On the main menu highlight Options and then hold down , , , and then . Make sure to turn on infinite ammo, infinite grenades, and infinite health. Also change the level to HQ. If you want the same map layout as me pick seed 53,215.

Next you will need to bring up the Backer menu. Go back to the main menu and highlight Options again and then hold down , , , and then and choose backer 7 Jacqui. Also select HQ as the starting area.

Make sure to change your difficulty to easy on the options menu.

Whenever you get into a new room position your second controller in the doorway and they will automatically knife enemies that enter, thus reducing the number of enemies that you need to kill. Occasionally a riot shield enemy will get through due to their shield. However, most of the time they will turn to face your second controller which allows you to easily shoot them in the back. A few times multiple enemies will spawn through the doorway and your second controller will only be able to attack one at a time so an enemy can sometimes get through. Your second controller will also distract a lot of enemies to make it easier to kill them. Your second controller will also always automatically follow you to a new room.

You will have to watch your health to see when you get hit. You can tell by looking at your character. If you see a flash of heart on your character then you got hit. You can look at 4:34 on the video which is when I got hit once for reference. Thanks for the reminder of this Zalexzy.

This was the only level where I found it easier to use two controllers due to the easy nature of the final boss. Other levels made the boss fight too long and risky.

Some tips to make a successful S run.
- An S rank run means that you can only get hit once. Your second controller can get hit an unlimited number of times.
- When going through rooms always go up when you can get a chance. Side rooms tend to only have survivors and will have a dead end.
- To get quick kills against any enemy throw your grenade directly at the enemy. A direct hit will instantly detonate the grenade to kill the enemy quickly.
- Prioritize the giant gun turrets that shoot in all directions. Throwing a grenade at them and getting a direct hit will instantly kill the turret. There is a cooldown period between grande throws. So instead of always spamming grenade use them wisely and wait for a gun turret to spawn, for there will be a lot of them in this level. In the event that you cannot throw a grenade you do have enough time to kill it with your gun, but you must start shooting it immediately. If you have a second delay you have the potential to get shot.
- After the gun turrets I found the riot shield enemies to be the second hardest enemy. I mainly used grenades to kill them, or shot them in the back when they were focused on attacking my second controller.
- Invisible enemies can sometimes go through walls, so be careful when you are behind cover.
- Always look at the floor to see any shadows. A shadow indicates that an enemy will spawn there. I had many failed runs because an enemy dropped on top of me.
- You can roll with , so if you are about to get shot try rolling away. Please be aware that if you are shooting it will have a second delay before you can roll.

Boss Battle
Phase 1
The only downside that I found to using a second controller is that the end game boss has twice as much health. However, the boss battle is significantly easier than the rest of the level. During the first phase often times the boss will only attack your second controller. If the boss attacks only your second controller, wait for the boss to pause its attack to shoot spiders at you and spam it with grenades. Be careful to avoid the newly spawned spiders. In the event that the boss attacks you, you can just run in a circle waiting for the boss to pause to shoot spiders at you, then spam grenades and kill him. As usual, the enemies such as the spiders tend to attack your second controller.

During the second phase of the boss you can position yourself in the bottom right corner and you will not get hit by the boss and you will rarely get hit by the spiders. Spiders will almost always attack your second controller.
* Clad Master mentions that it may be better to put your second controller at the left door. May be beneficial if you are having a hard time with the spiders with the boss.

I want to add my guide as I believe it improves on and makes The Forest and HQ A LOT easier but there are pre-requisites which require a PC to run this game and downloading REWASD

Initially you want to be playing this on a PC, the game is extremely low spec meaning most will run.

Plug in or connect two controllers as you need them.

Now download REWASD - it is a controller mapper and there is a free trial that I used which is good for 14 days. Boot this up go to the SECOND controller and select the LT button. Click Turbo and the software says this is a paid unlockable but also show you can trial the Turbo function for 3 days so select this.

This now enables your second controller to spam Grenades. Grenades not only kill enemies in one but also the blast blocks bullets which makes your second player a hell of a lot more useful. I found it best to position then as soon as I entered a new room in the middle facing up so the grenades bounce of the wall and blow up in the middle.

Boot up the game and then highlight the options on the main menu and enter LT+Y+left+start and put all the cheats on. Then LT+Y+right+start and select Jacqui Number 7 and the HQ level or Forest or whatever level you are doing.

Get your second controller LT held down somehow, I positioned mine with two heavy books either side with one pressing in the LT button.

Now do your best to avoid enemies, the grenade spamming from player 2 also helps with bosses and I did Forest and HQ using this method on my own.

Achieving an S Rank means you only can get hit once on this particular level.

I had much trouble in getting this achievement with the mentioned seeds by others. I was very close with seed 53215 but there are a couple of rooms which are highly luck-based and provide not as much cover as the seed I eventually used to get it:
Seed 44378
(credits to AvengedEvil over at True Trophies - https://www.truetrophies.com/t278532/hq-s-rank-trophy)

In other solutions there is mention of using a second controller to let the 2nd character shoot and spam grenades as well. I did the same thing but by playing the game on PC and using software to automatically press some keys.

I used an auto-key-presser (open-source, nothing fancy, see https://github.com/MissToxia/auto-key-presser) and I simulated this input for player 2: aaaaaaaaaaqwwwwwwwwwwqssssssssssqddddddddddq

So this makes sure the bot fires 10 bullets and one grenade in all four directions and then repeating itself. If needed, you can even use the cursor keys to reposition the bot without interfering with its shooting schedule.

Of course, there are probably lots of tools out there that can simulate it even better, but it worked flawlessly in my case

Still, even with this very active second player, the challenge is real. Like I said, I had so many attempts on the other seeds, before finally getting it on my third attempt at the seed I mentioned (44378).

Like mentioned in the other solutions, first take care of these steps:
- Open debug menu by highlighting Options and then hold down , , , and then
- Turn on infinite ammo, infinite grenades, and infinite health
- Change level to HQ
- Pick a seed that you're comfortable with, in my case 44378
- Open backer menu by highlighting Options again and then hold down , , , and then
- Choose backer 7 Jacqui (this makes sure you actually get to the final boss) and select HQ as the starting area
- Change difficulty to easy in the options menu
- Start a 2 player game
- Once in the room, start the simulated input for the second player by pressing the buttons Ctrl+O

And here for some basic tips during the different rooms:
- don't overspam grenades, make them count and go for direct hits: especially make sure you can instantly throw a grenade directly at the big turrets before they fire.
- position yourself first to safety (most rooms have cover), then if you are safe and have some time, reposition your bot a bit to focus on more sections of the room. But this step not necessary in most rooms and perhaps makes you focus less on staying out of cover with the main character.
- always be aware of the invisible enemies, as they can go through the walls.
- look at the floor for shadows of spawning enemies.

Last room before the boss fight:
- choose one side, kill the bottom left/right enemy first, then aim upwards to kill the other guys above. Then go up and down in avoiding the bullets from the other side and kill the others. Not too hard, but a tricky room in which you can get easily hit in the chaos of all the bullets.

Final boss room. This is the easy part, you won't get hit here if you do this:
- run around going from left below to upper right, take care of the spiders and then position yourself in the bottom right corner. The bot will take care of most here so just spam grenades/bullets in to the boss, taking care of any spiders as well by shooting in that direction: you won't get hit by the boss here.

I hope this solution also helps in more people getting this tricky achievement. If you have any feedback or if you need some help, please let me know. Good luck!