Last chance to save the world

*Using the DCTV characters*
After the battle for earth between the villains and heros they have finally exhausted each other and many have died in the ongoing war. The others still fighting have been caught off guard by brainiac who attacked city's across the globe. The flash is the only one fast enough to stop him goes back in time and warns the other heros and villains. Knowing the new threat looms they must work together (sort of) to even have a chance to survive the collector of planets strikes.
(Includes Kara x Barry, Oliver x laurel, Thea x Roy, Caitlin x Ronnie and more ships that may or may not be canon!) (major character death!!) (different timeline!!)