Omega has fully formed, and Vincent has fully transformed into Chaos. Shelke comes in with a neuro-network dive, finds the protomateria and fuses it with Vincent.
Many, many flashbacks through Dr. Lucrencia's eyes, and her formerly shattered consciousness reforms and confronts Vincent, snapping him out of his misery.
Goes controlled Devilman, and begins the fight.
After infuriating Omega's body, Vincent has a shoot out with the inner core, bringing out the now empty shell of a vessel, and shoots that too.
Omega tries to GTFO the planet, and the spirit of Chaos follows, destroying it for good, and saving the world.
Roll credits.