Hang/loop when attacking, related to Stinkweed Imp?

I'm experiencing an infinite loop/hang that happens as soon as I attack with any creature. It may be related to the Bushido ability, however given that it happens even if I attack with a creature with flying that can be blocked by Stinkweed Imp only, I'd be inclined to think that it's Stinkweed Imp's fault.
Savegame and screenshot attached. Thanks.
Savegame and screenshot attached. Thanks.