I would prefer it granting a Status Effect for its effect, ala Fortify, that would grant immunity to Slowed and additional armor since you're just about never going to clear all of the oil directly between you and your destination unless you're the one that produced it. More utility on already underused abilities could never hurt.
Last edited by GreatGuardsman; 20/10/17 11:34 PM. Reason: reduced wordiness