Okay, so like... Edmund fakes Gino Gambino's death, gives the photo and a bloody shirt with Gino's real blood to Crescendo to give to Luca the dark elf kid. Luca is summoning Nyx (I think), one of Gaia's five sons who was banished.
At some point in this weird a** story line, the eldest of Gaia's sons was eradicated. The youngest hung out with one the Titans created, the God of Ambition and they cause trouble.
The God of Ambition turns out to be Johnny K. Gambino, but he's stripped of his power when he confesses that he and Nyx were to blame for setting the Sentinel and the Overseer against each other. Nyx got banished and Johnny turned mortal.
Gino has Titan's blood in his veins, so Gaia tells him and now he has to fight Nyx in a weakened form as he's now possessing Luca's body.