Harry Potter, the Marked

Harry Potter, the Marked enters the battlefield with X +1/+1 counters on it.
Other creatures you control get +1/+1 and they have hexproof.
{2} Harry Potter, the Marked gains flying until the end of the turn.
{x}{r}{r} Harry Potter, the Marked deals X damage to target creature or player where X is less or equal to the number of+1/+1 counters on Harry Potter, the Marked.