Besiege

Here is a guide I have, but i'll also make a written guide.

*Should simply need to use a flamethrower and water gun to burn yourself/put yourself out.*
**However, achievement seems bugged at launch**

1. Start up any campaign level, the first one works great.
2. I built outwards in 4 directions, built pillars on the outside, and aimed flamethrowers towards one pillar in the center of the machine.
3. I then put a water gun on each side, aiming outwards.
4. I quickly turned on and off the machine, allowing the machine to catch fire and spread.
5. Once spread out, I turned the water guns back on, putting out fires at multiple levels of burning.