Greater Channel Smite

You empower your weapon with the might of your deity, which you discharge as you strike your foes.

Prerequisite: Channel energy class feature, Channel Smite, base attack bonus +8.

Benefit: Before making any melee attacks on your turn, you can use a swift action to expend one daily use of your channel energy class feature. The dice from your channel energy feature form a pool of damage dice you can access to further damage creatures normally harmed by the energy you are channeling—undead for positive energy, living creatures for negative energy. Prior ® ™ to making each melee attack, allocate dice from the pool to be used as extra damage dice if you hit. Your target can make a Will save, as normal, to halve this extra damage. This extra damage is not multiplied when you score a critical hit. If you miss, the extra damage dice remain in your pool, but any dice left unexpended at the end of your turn are wasted.

Source: Ultimate Combat