Here is the full list of all 19 Punkgrad achievements.
Take a sip of Dryan
Clean the mouth
Touch the phone
Take a flight on a rocket
Shoot yourself from a cannon
Finish the game
Kill a green microbe
Kill a red microbe
Kill the Microbe King
Kill a red matric
Kill a blue matric
Kill a purple matric
Kill the Matric
Kill a dogorocket
Kill a cheeser
Kill an alien with a katana
Kill an alien with a wavegun
Kill a brain
Kill Shakal