Here is the full list of all 12 Zombeer achievements.
Finish the game on Normal difficulty
Find all the developer diaries
Find all the "Men in thongs" figures
Find all the cover pages of Jessica
Get all the sniper rifle parts
Grind up three zombies in the turbine
Crush the president in the stadium
Complete the game without getting drunk or zombified
Find all the collectibles
Complete the game on Hard difficulty
Complete the game using only the dildo
Finish the game on Easy difficulty