Star Wars: The Clone Wars - Season 3 - Eps 16: Altar of Mortis
Before the Jedi can leave Mortis, the Son takes Ahsoka captive in an attempt to entice Anakin into joining him to use their combined strength to overpower his Father and Sister. To this end, the Son casts Ahsoka under the spell of the dark side. Meanwhile, the Father attempts to stave off a disastrous showdown between his children and maintain the Force's increasingly precarious balance on the planet. Fearing that the Son may be unstoppable, the Daughter does the forbidden by taking Obi-Wan Kenobi to the Altar of Mortis, wherein is kept the Dagger of Mortis, a weapon capable of killing a Force-wielder. The Son steals the weapon, and attempts to use it against his Father to steal his power and end his rule, but the Daughter sacrifices herself, placing herself in front of the blade.
About Star Wars: The Clone Wars

Title: Star Wars: The Clone Wars
First Air Date: 2008-10-03
Last Air Date: 2020-05-04
Status: Ended
Rating: 8.5/10 (from 2106 votes)
Language: EN
Seasons: 8
Total Episodes: 133
Network: Cartoon Network Netflix Disney+
Genres: Action & Adventure, Sci-Fi & Fantasy, Animation
Production Companies: Lucasfilm Animation, Lucasfilm Ltd.
Synopsis
Yoda, Obi-Wan Kenobi, Anakin Skywalker, Mace Windu and other Jedi Knights lead the Grand Army of the Republic against the droid army of the Separatists.
Cast

Ashley Eckstein
Ahsoka Tano (voice)

Matt Lanter
Anakin Skywalker (voice)

James Arnold Taylor
Obi-Wan Kenobi (voice)

Dee Bradley Baker
Clone Troopers (voice)

Tom Kane
Yoda / Wullf Yularen / Narrator (voice)