Joining game #1142659 on tokyo.
At some point in the game, all overlord images in my deck (hand and playing area) were getting replaced by the images of the cards I last played them as. Overlords were also cumulated with normal versions of the cards in my hand. I was still able to choose the card I want to imitate (I didn't test that though).
I have added a screenshot that shows the issue as attachment, sorry for the bad quality.