Viper did not in fact betrayed omen. Omen on the other hand, was on a kill contract to kill radianites who discovered radiant. Surprisingly he was willing to kill viper who is suspected to be his wife. Unfortunately omen messed up and while viper was using the usage of radianite or her poison, it spilled on him and you can see that it went through is protective class creating the three strikes on his face we know today. you can see it in 3:46, 4:19, 4:40 in the valorant trailer. Viper put him in a chamber and tried everything she can supposedly for the man she loves. She is a doctor overall. You can see her crying at 4:42 in the valorant trailer. And i think that's why she and sage has beef cause omen eventually died but sage resurrected him and he transformed into the new beast we know of him now. It was omen though who is the one who betrayed viper and that's why viper doesn't talks about it because she doesn't want to be reminded about that event and thus why she lives in isolation by herself. I think that's the reason at the end of the trailer omen said he would like to speak to viper personally because they are the one who knows

I don't think anyone betrayed anyone...Omen was sent to kill Viper. Viper ended up defending herself and turned him into an experiment. Remember he doesn't have any memory, so Viper holds all the answers. Wish they'd turn this into an anime!!!!I'd watch like crazy!!!