The Guardian's Inner Strength

This spell improves the prowess of the caster.  Attacks made by the caster are at the usual chance to hit, but every successful attack does maximum damage.  This spell works in addition to any other magic, abilities or items that enhances fighting ability.  This spell affects hand-held weapons, weapons hurled by the caster, or spells that deal damage.  It excludes damage-over-time effects, as well as missiles that are propelled by a device, such as a crossbow. 

At Higher Levels: When you cast this spell using a spell slot of 4th level or higher, the duration increases by 1 round for each slot above 3rd.