Kraken hunter

Gunfire 2 - {1}{g/u} (Whenever this creature attacks
you may pay {1}{g/u}, if you do, this creature deals 2
damage to target creature. Deathtouch, Infect
or other keyword abilities does not affect this
ability)
If this creatures gunfire ability deals damage to a creature with mana value 5 or greater it deals
twice that much damage instead