Here is the full list of all 22 UltraGoodness achievements.
Defeat the Office Guy
Defeat the Machines of Terror
250 bombs thrown by the player
Defeat the Tree of Evil
10 000 bullets fired by the player
Unlock all companions
100 bombs thrown by the player
50 bombs thrown by the player
Kill 5 000 enemies
500 enemies killed by flames
250 enemies killed by flames
100 enemies killed by flames
50 enemies killed by flames
5 000 bullets fired by the player
Kill 2 500 enemies
2 500 bullets fired by the player
Kill 1 000 enemies
Kill 500 enemies
Catch bunnies having fun
1 000 bullets fired by the player
Be friends with Satan
Kill 100 enemies