Marusayn, The Dark Mind

{2}{u/b}{b/r}: Target player discards a card at random. If it is a creature card place a +1/+1 counter on Marusayn and a -1/-1 counter on another target creature.
At the beginning of each player's end step, that player draws or discards cards until they have four cards in hand.
If you have exactly four cards in hand, Marusayn, has deathtouch and Flying.