Prince Zuko, the Firebender

Whenever Prince Zuko, the Firebender enters
the battlefield, if you cast it, deal {x} to target creature, where {x} equals the number of red creatures you control.
Whenever a red creature you control becomes
the target of a spell or activated ability, deal 3
damage to any target, then put a +1/+1 counter
on Prince Zuko, the Firebender.