Deceptive Illumination

(Drow of the Underdark, page 50, DnD 3.5)

[General]

Your innate power to create mobile light is far more precise than others'.

Prerequisite

Dancing lights as a spell-like ability.

Benefit

You can spend a daily use of your dancing lights spell-like ability to cast silent image instead. The illusion lasts for 3 rounds after you cease concentration, but otherwise functions exactly as the spell. Your caster level equals your class level. You gain one extra daily use of your dancing lights spell-like ability.