Zhixtirix, the Forgotten

Whenever a creature enters the battlefield under your control or attacks, deal 3 damage to target creature or player.
Whenever a creature or player recieves damage, put a +1/+1 counter on Zhitirix, the Forgotten.
At the beginning of your upkeep, for each +1/+1 counter on Zhitirix, the Forgotten, deal 2 damage to target creature or player.