Not tested, but i think you search this: https://github.com/TrinityCore/TrinityC ... .cpp#L5165
If you change that to 0, (ReqValue < 0 ? 0 : ReqValue) > irand(skillValue - 25, skillValue + 37)) a few lines below will become 0 > irand(), which is always false. Better change the conditions or choose something else than 0, like a very high value.