Vision (you have to see to apply the right rouge)
Dexterity (for application)
Charisma (to make the best use of it)
Knowledge (of the best rouges)
I apologize for the humor, but please understand: I used to deal with a bunch of rogues when I DM'd in an online game for years, and occasionally we'd get a new member who called the group "rouges." He/she'd be mercilessly pilloried by the other players, and I got to wincing whenever that misspelling showed up. I'll be quiet, and good now. [img]smile.gif[/img]