[This probably belongs in AI bugs - I didn't notice that forum before posting]
I used Prince on a Develop card (not a very smart move - for some reason I was thinking it would be optional and if I didn't use it the Develop would go back into my deck), so each of my turns started with trashing a card. Several times during the game, instead of prompting me to trash a card at the start of the turn the message said "Waiting for Lord Rattington". I could fix it with "/undo 1" - LR would repeat his previous turn and then I'd get the prompt to trash a card.
Game #2054. Screenshot of one instance is attached.