Basically an incrementally speeding up 2D shooter. All characters after killing turns into ragdolls, so you might need to hit them twice to move them from the screen - they might be annoying when the new character is already on the screen and on the same line as a ragdolled one.

Each killed character gives you 50 points, so you need to kill 140 of them for the achievement. More than possible if you can aim a little.

Snake. Don't try to get rid of your tail or you'll immediately fail. Put arrows beforehand to prevent early fail. Basically you can just move around, see the screenshot (also needs arrow up in the bottom left corner, and arrow right in the upper left corner).
Eat around 30 gems to complete.

Labyrinth. Follow the video (there might be a better way but I found this one so bear with it).










WARNING! In the end, follow this path. Another path might lead to the game crash (known issue).

Legit way:
https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=2741367061

Cheese way (thanks to Dogas):
The game is still working even after "Lose" screen. Just click the upper right corner (not exactly, but somewhere my cursor in the screenshot is) to launch the next wave - there's no indication so you can click this area each minute or so. Do it until you get the achievement. Might consume about an hour of a real time.