Board Thread:The Flash discussions/@comment-9346948-20170503000247/@comment-31577509-20170506022540

Here's a theory I have. After Iris' death, two possible versions of the future are created. The one we saw in ep 19, and the one that sees Barry becoming Savitar. In the second timeline, The Flash goes darker and ends up killing villains. He soon gets arrested, and meets someone in prison. His conversations with that person changes his outlook on like. He decides that the life of a human is miserable and pointless, and if he were to live, it would be as a god. Some point in time after gaining his new powers, he finds out that he is actually Savitar, and to ensure his existence he has to create his own origin, where he goes back in time, kills Iris and makes Barry go through the pain that will lead him to the dark side. There are a lot of hints that support this theory:

Barry to Iris: There is no Flash without Iris West.

Jay to Barry: There are infinite versions of the future, the one you saw just now may not be what actually happens.

Cisco to Barry: For every decision you make, a universe exists where you don't.

Savitar to Iris: Iris, I'm sorry you have to die, but it's you or me.

Savitar to Barry: I will kill you, but you will have to watch Iris die first. (He can only kill flash after his timeline branches off)