Anti-trixie, Dark Trixie, Mean Trixie, fuck call it whatever you want. She pledged to continue what Manerg had begun and started by killing Chrysalis. Manerg killed himself. Octavia was the only pony who attended the funeral, and she was relieved after being afraid that he would have eventually killed her.
I could have just corrupted the original Trixie, but that would have failed because her friendship with Starlight and the others was too strong and she would have inevitably turned on me.
Whether Anti-Trixie succeeds or not will forever remain a mystery, because I never lived to see it.