ROTDS beta testing

Ah, here we go again. Good ole ROTDS. It's been about a year since I've been able to play. Needless to say, the new first boss surprised me. And while I was active when we added the new map, I had forgotten about it. I got lost. Anyways, I'm to Spiral Mountain now, and everything seems good so far. I wanna refight Tritoch, though. Unless I'm mistakened, there may be something wrong with him. When I poison him, and he uses Rippler, it poisons one of my people, but I dont recall re-poisioning him, and he took poison damage. Which reminds me. Whats the trigger for that battle to end? Amount of time passed, or amount of damage done?