Mark of the Hunter

By pointing your finger at one of your favored enemies, you mark it with a glowing rune that only you can see.

(Spell Compendium, p. 138)

Originally posted on D&Dtools

Divination

Level: Ranger 3,
Components: V, S, M,
Casting Time: 1 standard action
Range: Medium (100 ft. + 10 ft./level)
Target: One creature, which must be a favored enemy
Duration: 1 minute/level
Saving Throw: Will negates
Spell Resistance: Yes

Your favored enemy bonuses against a foe with a mark of the hunter are 4 higher than they would otherwise be.

Furthermore, the rune limns your enemy, making the foe easier for you to attack. The subject of a mark of the hunter spell gains no bonus to Armor Class against your attacks from any cover less than total cover, nor does it gain a miss chance against your attacks from any concealment less than total concealment. Other effects that grant a miss chance (such as incorporeality) work normally.

Material Component: A bit of skin or bone from the relevant favored enemy type or subtype.