Farideh, Devil's Chosen 2UR
Legendary Creature - Tiefling Warlock (Uncommon) Dark luck—Whenever you roll a die, Farideh, Devil's Chosen gets menace and flying until the end of turn. If any of those result in a 10 or higher, draw a card. "A pact is a tool, not condemnation."
That's right, Farideh is now the UR signpost legend for dice roll-matters.
Would be cool if she got a +1/+1 counter on 20 roll
Or was smaller and had a lower CMC. All of the roll d20 cards so far are 3 - 5 and have a similary expensive activation cost. It'd be nice if she was down the turn before, so you could at least try to get value.