The Crew Motorfest

I didn't find this easy at all. Is very luck based but there a few things you can do to give yourself a better chance of getting this. Unfortunately I couldn't find games with crossplay disabled so you're going to have to play with pc players. Also, this may be easier with a crew who communicate but I finally got it on my own.

First off, car doesn't really matter. When you load in your plane nose dive fast to where there are bonuses. You want to prioritise yellow bonuses as they fill your ultimate which lets you transform. Hopefully your crew will grab one or two straight away. Then the most important bit of advice is to keep an eye out for bonuses whilst trying to isolate a single player. I can't stress this enough, there are lots of teams communicating and if you head to where there are multiple players you will get wrecked quickly. So find one player on their own (not yellow players, they're your team) and stay behind them to hit them from behind or from the side, don't try to hit people head on. So you are essentially hunting. You don't have to destroy a player to build your ultimate, just hit them. Now counter intuitively when you transform for the first time hopefully early in the game, you don't really want to destroy others. This is because the more damage you do whilst in a monster truck it prolongs your ultimate. We don't really want that as we want to get back in our demolition car to start building our ultimate again. So after the first one is done is the tricky part. Hopefully you can get lucky with a couple of item drops, if not then you're going to have to hit some players. Keep an eye on your health, and still try to target lone players but as the arena shrinks you may find yourself in unavoidable battles.

Eventually, with some luck, skill, and a half decent team you should be able to grab this achievement. Probably took me 20 goes before I managed this (with some near misses beforehand)