Devovorga's Essence Mini World Change/Spoiler

Messages
World Board: In case you have some spare tentacle pieces, you can now use Devovorga's very essence to enter a boss lair!

Towncryer: Hear ye! Hear ye! Use Devovorga's Essence to fight an evil presence! Trade your every tentacle piece, to enter a boss' lair with ease!

Method
When this Mini World Change is active it's possible to enter the teleport in Vengoth here. In there you can get the chance to fight Devovorga's incarnations in exchange for Tentacle Pieces.