Rebel Thievesmind

Skulk (This creature can't be blocked by creature with a greater power than this creature.)
Whenever Rebel Thievesmind deals combat damage to a player, that player Mindwipes 3. (To mind Mindwipe 3, put the top 3 cards of your library into your graveyard.)
Undercover {u/b}{u/b} ({u/b}{u/b}: Turn this creature face
down as an 0/1 creature with shroud. You may turn
it up at any time for its Undercover cost.)