In the pencil and paper version, if you roll a 18 on strength, you get to a 100-sided dice that determines the str bonus you get for having 18 strength. The numbers affect your THAC0, extra damage dealt, how much stuff you can carry, and your chances of forcing open a locked door or trunk.
You only get the bonus if you're plaining a paladin, ranger, fighter, or barbarian. Possibly monks too, I don't know. All other classes just get a basic 18 in strength.
18/01 and 18/50 are identical in terms of the bonuses you get, everything within that range will give you a +1 to hit, and +3 to damage.
18/51 to 18/75 will give you an extra +1 to hit.
76 to 99 gives a total of +2 to hit and +5 to damage.
18/00 gives you a +3 to hit and +6 to damage.
There is suppose to be a bashing percentage thing involved as well according to the manual, I dunno what that means, I guess it means your chances of interupting spell casting.
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