Channel Smite [two-actions] (Feat 4)
Cleric    divine    Necromancy
Prerequisites harmful font or Healing font
Cost Expend a harm or heal spell.

You siphon the destructive energies of Positive or Negative energy through a melee Attack and into your foe. Make a melee Strike and add the spell’s damage to the Strike’s damage. This is Negative damage if you expended a harm spell or Positive damage if you expended a heal spell.

The spell is expended with no effect if your Strike fails or hits a creature that isn’t damaged by that energy type (such as if you hit a non-undead creature with a heal spell).