Here is the full list of all 11 Moose Life achievements.
Create more than 350 stags in one level
Obtain all the achievements
Butt an enemy to create a trippy stag
Get a herd of 1000 stags
Get a herd of 10000 stags
Get a herd of 500 trippy stags
Create a rave of1500 trippy stags
Take a poison mushroom trip
Get the maximum number of lives
Go from a gate to finishing the level without firing a shot
Finish the game