So I have 2 Ghostly Prisons on the Field and somehow the person I'm playing against who is all tapped out of mana is able to attack my planewalker with their creatures?!?!?!

I checked the board and there is nothing they can tap for mana and no abilities that could allow them to attack .

The player's name was EdamameCheese.

I think they were cheating somehow. I have it caught on stream.