Darkseid supposedly leaked as Injustice 2's pre-order bonus character, similar to Goro for Mortal Kombat X
For those that don't recall, the way it worked was that a code was given to players that pre-ordered the game that unlocked Goro for free at launch. For those that did not, they would have to pay an additional fee in order to unlock Goro.
In Injustice 1, we only saw Darkseid as part of a stage transition and at the end of certain individual character story modes. It's worth noting that even though Goro was available at launch, Goro was not apart of the game's main story mode.
Hopefully Darkseid will have an impact on the story mode, unlike what Goro was to Mortal Kombat X's story.
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Sent in by: SqueakyBloom, SnakeX, originalhuman.