Return to the Plague Tower

Steps
Clear the grounds - Defeat 25 of Gyrion's minions

Place Three Orbs - Orbs can only be placed one at a time and a short fight occurs after placing each one

Step on the Pad - Step on the pad in the center of the room. (Don't worry about the root effect, you're only being infused with Spellplague Energy. What's the worst that can happen??!!

Return to the River District