Attribute Checks Option

With attributes reaching to a score of up to 30 (I don't allow attributes to exceed 30) and no clear rule on how to roll a check against these massive attributes (i.e., a straight D20 v. Score check just wont cut it) I have come up with a way of handling checks:

(Attribute score x 3) / 5 = Check #

With an attribute score from 3 - 30, multiplying it by three will give a result of 9 - 90. I tie this result to a percentile system leaving a ten percent gap at the top as a margin of failure even for those with attributes of 30 (my game's maximum).

Now to take this and turn it into a simple D20 check number, divide the result by 5 (rounding up). This gives you a number between 2 and 18 which you can check against a simple D20 check (applying modifiers where appropriate).

E.g., Hestor has a Physical Prowess score of 23 and is about to walk across a sloped surface that is covered in loose debris. We multiply his attribute score by 3 giving us a result of 69. Now divide that by 5 for a result of 13.8 which is rounded up to Check score of 14. So Hestor's base target when checking his attribute against a D20 would be 14, but since the surface is sloped and covered with loose debris, we will hit him with a modifier of -6 (GM discretion representing the difficulty of crossing the surface).