Since the merger, Crunchyroll is the primary home for the Dragon Ball franchise. You can find the "The Final Chapters" arc (which includes episode 140) there.
This episode highlights Buu’s unique biology—his ability to regenerate from almost any damage and his "innocent" but deadly nature. Quick Guide for Fans Watch Dragonball Kai 140
Most platforms offer both the English Dub (featuring the classic Funimation cast) and the Japanese Sub (original audio). Since the merger, Crunchyroll is the primary home
After being resurrected by Babidi, Majin Buu begins to showcase his terrifying and unpredictable power. The Z-Fighters, particularly Gohan and the Supreme Kai, realize the gravity of the threat as Buu easily overpowers them with his childlike yet brutal fighting style. Since the merger