Casey Jones, Back Alley Brute

Flying, vigilance

Whenever one or more +1/+1 counters are put on a creature you control, Shalai and Hallar deals that much damage to target opponent.

Whenever one or more artifacts you control enter, this creature deals that much damage to each opponent.

Haste

Whenever this creature attacks, put a +1/+1 counter on target creature you control. Then this creature deals X damage to each opponent, where X is the number of modified creatures you control other than this creature. (Equipment, Auras you control, and counters are modifications.)

When this creature enters, put a -1/-1 counter on target creature you control. This creature deals 3 damage to target opponent or planeswalker.

Whenever you put one or more counters on a permanent or player, this enchantment deals that much damage to target opponent, creature an opponent controls, or planeswalker an opponent controls.

Whenever an instant or sorcery spell you control that targets only a single creature deals damage to that creature, Imodane deals that much damage to each opponent.