If Luminara Unduli is dead, then what was that thing sitting in her cell before it became her corpse? A hologram or a spirit? Creating even more Fridge Horror from people's knowledge of the Legends continuity, there is a Dark Force technique for controlling the restless spirits of the dead and keeping them from becoming one with the Force until the user feels like it (and used by another Inquisitor). If that still applies canonically, then Luminara isn't entirely dead and the Inquisitor is using her faint life-force as bait for surviving Jedi while keeping her spirit shackled to a rotting corpse as a Soul Jar. Cessation of Existence might not be as horrible a fate as the Sith make it out to be after all, yet they have a very twisted way of enforcing that idea.
Removed due to new revelations....
Dave Filoni weighed in
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We were watching a hologram. It was a recording of her execution by the Inquisitor.
Edited by 70.31.201.6