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