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