When you have Edgar Markov on the board, and your blood token gets destroyed (as in completely destroyed, not just loosing one shield), it triggers, creates a vampire token, which trigger Edgar to create a new blood token, and the blood token gets stuck on the screen. It is pretty rare for the blood token to get destroyed while Edgar is on the board (basically has to be by a spell, because Edgar keeps replenishing it), so I don't encounter this very often, but I play with Edgar often enough to be pretty sure that this happens consistently.
its a floating card. been very difficult to fix. @Magic:PQ Support Team maybe something y'all can fix??
https://forums.d3go.com/discussion/78614/floating-card-issue-workaround-investigating
animations off do help but some of us like our animations on auto