Here is the full list of all 12 Zombiezz trophies - there are 11 gold and 1 platinum.
Collect all trophies in game.
Kill a zombie using rifle power up.
Kill a zombie using rocket power up.
Kill a zombie using grenade power up.
Kill a crawling zombie.
Kill 5 zombies in a level.
Pop a killed zombie's head.
Collect armor power up.
Collect health power up.
Kill half the total number of zombies
Destroy an obstacle using gun or grenade.
Complete a level by killing all zombies.