Level: Ranger 1
Components: S
Casting Time: 1 standard action
Range: Close (25 ft. + 5 ft./2 levels)
Target: One creature
Duration: 24 hours/level
Saving Throw: None
Spell Resistance: Yes
With a wave of your hand, you cause a tiny mark to appear upon the target’s forehead. “I will know you in any form or visage,” you say.
This spell marks your target with a tiny symbol visible only to you and to detect magic. The brand appears as you envision it, approximately 1 inch in diameter. You can see the brand even if the subject uses magical means to change or hide its appearance. Spells such as disguise self, polymorph, and invisibility do not hide the brand. To your eyes, the mark glows a light green.
Source: Spell Compendium, page 204.