Cthulhu, the Dark Abyss

When Cthulu enters the battlefield choose one:
• Flip a coin for each other creature on the battlefield, for each tails sacrifice that creature
• You gain life equal to half rounded up the
number of creatures on the battlefield,
each opponent loses half of that rounded down
Everytime a player would draw a card they flip a
coin for each card, for each tails they lose 1 life
instead