Here is the full list of all 16 The Wizards Who Fell In A Hole achievements.
Defeat your first boss
Complete your first level
Get half way through the game
Complete the game
Find the elusive Battenberg
Eat 250 pieces of food
Eat 500 pieces of food
Eat 1000 pieces of food
Eat 2500 pieces of food
Score a million points
Collect each type of special item
Collect 50 special items
Collect 100 special items
Kill 500 monsters
Kill 1000 monsters
Kill 2500 monsters