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Realistically, how many more characters do you think will get added to Origins before letting it die?
There are 11 more characters from vintage MotU to remake after the upcoming Dragstor:
Two Bad, Multi-Bot, Stonedar, Blast-Attak, Rotar, Twistoid, Saurod, Blade, Gwildor, Tytus and Megator.
A Mattel employee said "Filmation isn't over" when the 200X refresh was shown off at SDCC, so we can expect that subline to get Mattel Creations slots. And both will have to share slots with other things like Axel OCs (pic related).
I would guess at least 20 characters, not counting variants of existing characters (like Laser He-Man/Skeletor) before Mattel pulls the plug.