Reverse Flash (New 52)'s History
Daniel West's mother died giving birth to him, a fact for which his father William never forgave him. This also drove his father to become an abusive alcoholic. His sister Iris protected and supported him until the day his father went too far, and an angry Daniel pushed him down the stairs, crippling him for life. When he realized that Iris' opinion of him would change forever as a result of those actions, Daniel ran away from home, blaming his father instead of himself for what happened.
By the time he was eighteen he had fallen in with a fast crowd, becoming a small-time thug. All while trying to mend his relationship with Iris, who resented him for leaving her with their paraplegic father. His first big score was thwarted by The Flash, and he wound up in prison for 5 years.
When he got out of prison, Daniel found that Iris still was not ready to make amends with him. While he struggled to make it on his own, he was captured by Gorillas when they attacked the Gem Cities. When he was rescued by the Rogues he learned that they still intended to rob those they had saved. In his attempt to escape them, he crashed into Dr. Elias' stolen monorail car, which was powered by a Speed Force battery. The accident imbued him with the ability to turn back time, but that power was dependent on the Speed Force charge in the battery.
Wanting more than anything to go back in time and change his relationship with Iris by killing his father, Daniel dubbed himself the Reverse-Flash and began murdering those who had been touched by the Speed Force in order to drain them of the energy he would need to go back in time far enough to change his own past.
Eventually, the only ones touched by the speed force who remained were the Flash and Iris. The Flash had learned that Daniel could not sense him through the Speed Force because of his containment suit and gave one to Iris to mask her as well. Not to be deterred, Daniel managed to lure the Flash to Doctor Elias' lab. He used his power to go back in time — to the day of his last happy memory when he was eight years old — and kill his father. His plan backfired though when his younger self and Iris come home just in time to witness his act of murder.
Daniel attempted to kill his father while the Flash defended his and Iris' younger versions, only to realize that he was causing them more trauma. With the Flash's convincing, Daniel gave his powers up to the Flash to let him fix his mistakes. The Flash managed to do so, and he brought them both back to the present, without any repercussions of their actions to the timestream. Iris held the weakened Daniel, who told her that he still did not regret trying to fix things between them by killing the others. Daniel was then sent back to Iron Heights. Daniel continued to defend his actions to Iris, who was still disappointed and turned her back to Daniel for good.
New Suicide Squad
Daniel is recruited for the Suicide Squad, apparently having regained his powers. While he is fast, he is remarked as not being nearly as fast as the Flash. During a mission where he is asked to plant bombs, Daniel overexerts himself and blows out his knee. Later, the Squad are heading back to headquarters after finding a time bomb in a village. Daniel decides to be a hero and runs back to the village to save the children by getting rid of the time bomb in the ocean. He is able to drop the time bomb in the ocean, which detonates, and he seems to be able to make it back to the group. Unfortunately, he trips and rolls while running back on the water, and is sucked into a vortex created by the time bomb. The skin on Daniel's hand comes off, leaving a skeletal hand, and Daniel supposedly dies as a hero.