Belos possesses the Titan

After hitching a ride in Raine's body, Belos makes his way to the castle, and despite Raine's best efforts, fuses with the Titan's heart in order to possess the entirety of the Boiling Isles. The entire island quickly becomes overrun by rapidly growing lichen, choking out and consuming all life, and Belos fashions himself a body that more closely resembles a dragon in order to "cleanse this perdition himself".

Example of:
The Corruption