Calibrum, The Hitman's Rifle

Equipped creature has +2/+0 has reach
and {t}: This creature deals 1 damage
to any target.
When equipped creature deals damage to a
creature without a Mark counter put a Mark
counter on that creature.
If damage would be dealt to a creature with a
Mark counter on it Double the damage and
remove all Mark counters from that creature.
Equip {2}