Ability Checks made Easy

Ever had to make an ability check? Ever found out that it's impossible to fail, because you have a 21? I was letting some thoughts run through my mind today, and I think I came up with a very simple method of doing ability checks. All you do is roll a d20, and add in your ability score. If that's equal to or greater than some number chosen by the GM (about 20 is an average task), then you succeed. If you roll a 20, roll again and add the numbers together (keep rolling until you don't get a 20). If you roll a 1 and still succeed, then something has gone wrong, but it works out, anyway. If you roll a 20 and fail... well... pucker up, because you need to polish your GM's butt with your lips in order to survive.

For example: Triath is trying to open a jar of peanut butter that Brand has just put away. Now, Triath isn't that big (PS 10), and the GM feels like being a pain in the butt, so he makes him roll, setting the number at 25 (probably because Brand put the peanut butter jar in vicegrips and tightened it with a wrench... he's protective of his peanut butter). Triath rolls a 5, not even coming close. He throws the jar at Brand, telling him to open it.

Brand's a bit bigger, having a PS 16. He takes a hold of the jar, and twists with all his might... but his player rolls a 1. Brand's hand slips, and he slices it open on the counter. He curses and throws down the jar, telling Triath to open his own damn peanut butter, as he goes off to find some band-aids.

Triath, however, still has no peanut butter, and he's really looking forward to a peanut butter and jelly sandwich. He goes off to find Bishop, the strongest guy in the house. Bishop has a PS 24. He wraps the lid of the jar in the front of his shirt for a better grip, and turns with all his might. In another bit of bad luck for the night, Bishop's player rolls a 1. However, since Bishop has a PS of 24, that still adds up to 25, meaning he succeeds... but not without a mishap. Bishop, it seems, is so strong that he accidentally rips the top off the peanut butter jar, including the lid and about 1/3 of the jar. While Bishop goes to wash his hands, Triath goes to make his peanut butter and jelly sandwich.
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