Warning: This post contains SPOILERS for Mortal Kombat 2021.
In 2021's reboot of the Mortal Kombat movie franchise, Scorpion takes center-stage, despite the fact that he's killed off inside the first 13 minutes, so how does he return? Though he is comparatively sparsely used throughout the runtime of Simon McQuoid's action-heavy spectacle, his shadow hangs over the entire story thanks to his ancestral relationship with franchise newcomer Cole Young (Lewis Tan). But the reality of how he's able to defy the grim reaper and return from "Hell" as he says he was sent on death is a little less obvious in the movie.
Mortal Kombat is, somewhat typically, heavy on lore, but the limits of a traditional cinematic runtime mean that there's a lot left unexplored about the original fighting game universe. While the Elder Gods are referenced, they are part of a far richer tapestry of story and lore and if the franchise continues into Mortal Kombat 2 and beyond, there's a greater opportunity to peel back the layers on more of the realms. That will, hopefully, guarantee an expansion of Outworld lore as well as that of other interesting realms like the Netherrealm. Crucially for the latter, Mortal Kombat's Scorpion has already set-up its existence without overtly confirming as much on screen.
The Hell of Mortal Kombat is very likely to be the Netherrealm of the canonical games' lore, particularly as McQuoid's movie sticks so close to lots of the lore of the later games in particular. And in that realm, reincarnation is established as possible, in Scorpion's own backstory. At one point Lord Raiden resurrected him using his magic (in Mortal Kombat X), but even more importantly, Scorpion's status as a specter means that he is somewhat immune to death. He is bound to life by his revenge, and the death of his family in the prolog of the movie suggests this franchise is following the same logic. In a broader, sense, the idea of vengeful reincarnation is a parallel of the Chinese belief in the dead returning if they have unfinished business. That compulsion is what brings Scorpion back in Mortal Kombat too.
As in Abrahamic religious lore, Hell is the place of eternal damnation, where the souls of those who have committed crimes are sent to be tortured. But Scorpion wasn't established as evil in Mortal Kombat's prolog, despite and his alignment against Sub-Zero and Shang Tsung by extension seems to suggest moral goodness. In the game lore, Scorpion became a vengeful specter in the Netherrealm, when he was killed by Sub-Zero, but was never evil (nor was he good), suggesting that like the games, in Mortal Kombat, Scorpion is cursed in death to live in one of the higher levels of Hell. That would fit with his claim that he harnessed the fires of Hell, as the higher levels allow the damned to withstand torture far easier. Add his vengeful spirit and Scorpion had significant inspiration to find his way back to the land of the living.
For Scorpion to be completely resurrected would take something else, particularly now that his revenge is seemingly dealt with (though Joe Taslim's five-movie deal suggests Sub-Zero will be back for sequels) and he should have peace. Mortal Kombat X sets a precedent that Raiden's powers could manage it (he is a God, after all), or the brief appearance of the Amulet of Shinnok in Mortal Kombat (when Kano attempts to steal it) could offer an alternative pathway, as the artifact is capable of resurrection. For now, though, the solution to the mystery of Scorpion's revival is his pain.