Unstable Summoning

At the beginning of each upkeep, flip a coin.
If it is "heads", create a 2/3 black
Cleric creature token with, "When this creature
dies, each opponent loses 1 life and you gain
1 life. Draw a card".
If it is "tails", create a 3/2 blue and black
Wandering Mage creature token with Hexproof
under the control of target opponent.
{u/b}{u/b}{1}, Sacrifice a creature: Destroy target
creature.