Void Merfolk

When Void Merfolk enters the battlefield, you may discard up to 4 cards from your hand.
If you discard 1, Void Merfolk gets a +1/+1 counter on it.
If you discard 2, Void Merfolk gains hexproof.
If you discard 3, Void Merfolk becomes unblockable.
If you discard 4, Void Merfolk gets a +1/+1 counter on it.