Forum:KB:The final end of Darth Maul

The Phantom Menance shows that Darth Maul was defeated by Obi-Wan Kenobi on Naboo. Yet, in the fourteenth episode of the third season of Star Wars: Clone Wars, mother Talzin, leader of the Nightsisters of Dathomir, orders Savage Opress to search for a brother in the Outer Rim in exile, while a kind of crystal ball shows the face of Darth Maul. So, my doubt is, what is the true end of Darth Maul during this period of the history of Star Wars?