Halo Infinite

For this achievement, start by finding a Razorback and then get in the driver’s seat. Next, honk the horn. It should be one continuous honk, so hold down your honk button. After this, have 3 people quickly jump in, one in the passenger seat and then 2 people in the back. After all the seats are filled up, achievement should then pop!

It is important to note that you must honk first with no one in the Razorback and then everyone can get in. I’d say honking for 2-4 seconds should be good enough.

To get this achievement, start a BIG TEAM BATTLE game and find a RAZORBACK. It's a kind of Wartog but without a turret.

Get in the car and have 3 other players on board (1 passenger side and 2 at the back) to unlock the achievement.

Please note:
- you must be the driver of the vehicle,
- you all have to get on board in a short time.

The method is explained in the other guides - however I'm just adding that a "mount up" medal will pop up on screen when you achieve the criteria. If you're trying for this and the achievement doesn't seem to unlock, it's likely that you didn't honk before loading people in so the medal (and achievement) won't pop even if you fill the vehicle.

Good luck!!

Best mode if you are doing this alone is Big Team Battle “BTB” Capture the Flag “CTF. You need to find a Razorback, which is a grey vehicle that looks like the Warthog, but it has no gun on it.

Next drive it to your base and wait there until 3 people get in the Razorback. Honk the horn at them to get their attention by pulling the shoot trigger.

If you have friends set up an Xbox Live party or if on PC do so with Steam or anything similar and repeat the steps above.

One Flag CTF on the map Kusini Bay in the new Workshop: Squad Battle Network playlist has a shrunken Razorback that only has 2 seats. Once the passenger loads the achievement will pop.

So I had to look to make sure no one had posted about this and apparently not but, if you load into firefight and get a map that has vehicle spawns and spawn the razorback you can actually pop the achievement with one other person in the vehicle idk if it because of the mode or luck but the achievement will unlock without having to go onto multiplayer and hoping people will get in

(Please leave a comment if you have gotten the achievement this way or let me know how it pop because I just got the achievement to pop with only one person in the vehicle and nothing in the back)

This achievement is actually fairly easy with the new Firefight in matchmaking playlist.

Other guides say BTB is the best way to go, however, with the recent update, Razorbacks now appear on Fragmentation, Highpower and Kusini bay firefight.

Each firefight match only lasts 2-3 minutes, as you can just get yourselves killed off the spawn and end the game quick if it's not the map you need. Be careful not to just nade spam the floor or jump off the map as 343i does ban players for unsportsmanlike behaviour.

Here's what I did:

Part 1

1) Create a Gaming Session via True Achievements/ Halo Discord asking for 4 players to join.
2) Queue into Normal/Heroic/Legendary Firefight.
3) If it's a map known to have a Razorback, see Part 2 below. If not:
4) Head straight towards the phantom that spawns, or the hill. The enemy will shred you on Heroic or higher, on Normal the phantom side turret will kill you quickly regardless
5) Repeat

Part 2

1) Take the razorback well away from any enemy spawns/ the hill.
2) All players stay out of the vehicle, driver enters first and spams the horn button repeatedly and continuously. Once the prompt shows up, all other players immediately enter the vehicle, driver drives forward to get the "Mount up" medal.
3) Cycle through the drivers until all players get the achievement.

Things to note:

Each Menu -> Load -> Game -> Menu is approximately 2-3 minutes. Much faster than BTB and without the risk of being disrupted by teammates or the enemy.

The Banished AI will capture the hills. Ensure they don't capture any hills to keep the game going if necessary.

Heroic gets you killed faster, Normal allows you quick travel to the Hill. Choose whichever is your preference.