Reaper, Devourer of Souls

+3: Deal either 3 damage or 6 damage to up to 2 Target creatures. If you chose 6 damage, have your opponent blindly pick a card, and discard it.
-4: Return Reaper, Devourer of Souls to your hand. This ability can be used on your opponents turn. If it is, Reaper cannot use any ability next turn
-X: Do X amount of damage to any number of Target creatures, and gain Y health. Y = Half of X, rounded down