As the Netherworld Turns Aladdin : Season 1 Episode 70

Iago uses a magical diamond in Jafar's old tower room on another thievish treasure hunt. But it proves a portal, which makes him and Abu immaterial, semi-trapped in the netherworld with the sultan's late father Bobolius. Worse, evil sorcerer Ayam Aghoul sees them as his way out, or at least for revenge on all of Aladdin's gang.