Below is a walkthrough for the Ancient Powers (Part 4) side quest in Tiny Tina’s Wonderlands. To obtain this quest, speak with Dryxxl after completing the Ancient Powers (Part 3) side quest.
Summon Dread Lord
Speak with Dryxxl when you’re ready to begin the fight. Defeat him.
Sacrifice life essence
Yet again interact with the object in the middle of the room.
Take reward
Grab the item to complete the quest.