Here is the full list of all 33 Boo Bunny Plague achievements.
Beat the game on Impossible mode!
Collected All Audio Lore in one game.
Collected the Frankenstrat.
Triggered Faye's transformation
Stun Thor 10 times with his own hammer.
Burn enemies 50 times.
Bounced on vikings 50 times
Hit the giant donut!
Collected the Streetz guitar.
Destroyed all of the Bunny's in the factory
Watched the entire after credits scene
You collected all of the coins in the credits
Defeated the Chairman
Unlocked Impossible mode!
Defeated the Secretary
has defeated Thor, Garmr, Hel ,Tyr and Heimdall
Defeated Heimdall
Somehow managed to fall through the world and hit a kill zone
Defeated Death
Defeated all Four Horsemen of the Apocalypse
Defeated Famine
Defeated War
Defeated Pestilence
Collected the Electric guitar.
Defeated Tyr
Defeated Hel
Collected the Ice guitar.
Defeated Garmr
Defeated Thor
Collected the Fire guitar.
Used Gunny to defeat an enemy.
Collected the "Useless" Acoustic
Defeated TRex