Goop pots everywhere and he's 10x easier.
I do not not play ops much at all but needed to a while back to level up a few chomps on alt 2 and to 100% the game. I recall beating two Yeti's by myself in open mode(normal level) hoping people would join. Also a triple boss wave on crazy difficult with 2 players against 3 Yeti's, AC Perrys and Artic troops. When solo or with other players I always leave empty pots/bots. Depending on which boss or bosses show up on the wheel of misfortune this determines the spawnables I then deploy. In both cases above I deployed 4-5 doom shrooms near the garden and scaredy shrooms at a distance. You want to basically run the distance away from garden and then back. When he stops to battle pots, attack quick and move again. On solo I did it with armor chomp, green goop and vamp weed. A trick can be used to walk through vamp weed when battling a boss to give you a health boost. I do recall using one auto revive playing solo and the max amount I could use on crazy mode. The key with the Yeti Boss is to attach his back side when he is busy with pots or even teammates and or AI.
