we played that the attacking creature's dice are used. The exact number of dice the attack would have used if successful are used for the redirect. The only modifier to this would be the +/- Damage trait. So let's say my creature X attacks your creature Y with a fast action attack with 5 dice. It's a lighting attack so I have the lighting ring and get +1 red die. You are lighting -2, taking away 2 dice, and thus giving me a result of 4 on a successful attack. Once I attack though, you flip your reverse attack card and so the attack comes back at me. It's still 5 base +1 for the ring, but since I don't have any bonuses or negatives against lightening myself, you know roll 6 dice against me instead of four.