I think this issue been posted but here goes.
Using Maw in battle seem to trigger this.
When down 2 one enemy unit it wont attack that unit to win battle.
Seems to be a ghost unit you cant see at the top of the board.
When enemy gets a skull match damage is diffrent than the unit showing,
Magic attacks lets you select the shown unit but does no damage
What platform are you playing on?
@Nimhain
Sorry bro posted wrong spot.
Playing on andriod