Yu-Gi-Oh! GX Episode 145: Summon the ultimate forbidden god, Exodia!
Episode 145 of 180 of Yu-Gi-Oh! GX, aired July 18, 2007, 25 minutes. Available with English subtitles and dub where released.
Episode summary
Adrian reveals that in order for him to claim Exodia, he must sacrifice his closest friend, Echo. Aster tries to stop him, but fails. He tells the rest of them to get out and save themselves. He ends up going to the stars and Adrian goes away riding on Exodia's shoulder, going to become ruler of that land.