As shown in the Absolute Conspiracy, Absolute Tartarus is a powerful being, capable of manipulating space-time to his very will. But a question in my head is Who just is Absolute Tartarus.
It is confirmed The Absolute Conspiracy takes place before the events of Ultraman Mebius (series), due to Alien Empera being alive. This would mean before the events of Ultraman Ginga. But why did I mention Ginga? I feel that Absolute Tartarus IS Ultraman Ginga (character), albeit before the split with Dark Lugiel. We have not seen Ginga yet in the whole series, nor Lugiel. We also have no idea what Ginga used to look like. So Tartarus has a chance to be Ginga.
From the words of Matpat: "But hey, that's just a theory, a Film Theory!"