Ace High

Once this spell is cast, for the next ten minutes, your d20 rolls are reversed. A natural one is the best you can get, and a natural twenty is the worst. Ability scores are reversed as well. For example, a +2 Wis. modifier is now worth -2, and vice versa. A 15 on a d20 is now a 5 and a 3 is a 17. The higher level you are increases the time by 5 minutes for every level higher you climb.