Hi, my name is Savitar. I know, you see me as a monster, trust me, I've heard it before. I wasn't originally called Savitar. I was Barry Allen, until my future self goes back in time to stop Zoom. I died, and it would have stayed that way, had Barry not created Flashpoint. In 2020, Barry Allen creates time remnants to help stop me from killing Iris.
I killed all of them, but one: me. Not only had I died, but now Team Flash had shunned me because I wasn't the "true" Barry Allen. I was an aberration, a mistake, an abomination, blah blah blah. It was then that I realized the truth: God feels no pain, all I had to do was become one, and so I found the Philosopher's Stone. Of course, with anyone wanting to become a God, he needs followers, and so I went back in time and spread my message across time, and the multiverse.
I created Alchemy to be my right-hand man, and of course Julian betrayed me. I turned Wallace into a speedster to be my right-hand man, and of course the kid betrayed me. When Caitlin Snow became Killer Frost, well, I seized the opportunity. Finally, I had a right-hand man by my side. I didn't want to kill Iris West, but I had no choice. For my ascension to happen, Barry had to be driven so far into the dark that he becomes me, and he must create time remnants to stop me. I considered killing him at some point, but I couldn't risk it, so I decided to kill the precious Iris West instead.