Here is the full list of all 10 Pixel: ru² achievements.
Complete all the levels of the tutorial with a positive score.
Set an enemy on fire through a barrier using the Burn weapon.
Kill an enemy with a fully charged Rico.
Kill four enemies (one in each direction) within 360 cycles (3 seconds) using the Sniper weapon.
Kill two enemies with a single Rocket.
Hit three enemies at the same time with the Spray weapon.
Jump or flip off of an enemy projectile.
Change the color of a projectile while in flight so that it will now damage an enemy.
Change into all 8 colors within 5 seconds.
Cause the bug where you fall inside of another entity.