Ran across this issue a few moments ago. Using an all beast team (Pignius died and his corpse was stomped by Hopper already).
Anyway, it’s my turn, but as you can see from the screenshot, the game doesn’t seem to know that. Whenever I try to attack, no matter who I target, it just says “invalid target”. I can’t do anything. And since Solaris is about to resurrect, I’ve got a pretty good chance of winning this and extending my streak. But now my only option is to retreat and lose my PVP streak.