Betting it's going to be Zoom with a whole type of storyline about "I'm nothing without you, and in the future you vanish, leaving me with nothing blabla (joker/batman type of scenario)." So he wants to go back in time and create the perfect nemesis, aka the perfect hero, and prevent The Flash from vanishing/dying/whatever in the future and so helps Barry in his own bizarre way. Betting he killed Barry's mom. Dude is just too creepy/evil yet altruistic at the same time and I think that hints towards his noble goal not truly having noble intentions.
Anyhow, that's just my speculation.