Encountered an infinite loop due to some kind of interaction between Marshall, Follow the Leader, Spur of the Heavens, and Heavy Repercussions. The last action taken was an enemy monster (a Diabolic Observer, but it was fused to something) attacking my team. Then Marshall and Follow the Leader notifications began popping up repeatedly, and my creatures began to reorder themselves in a loop at the bottom of the action queue. I held turbo for probably 3-4 minutes without reaching an end point.
EDIT: Just had it happen again. Marshall appears to be placing my creatures in last place instead of first whenever it triggers now.