math for this is wrong:

Refining Rebate (Low/Medium/Advanced Refine Runes)

10 Times - 1 Advanced Rune - 10%

50 Times - 5 Advanced Runes - 10%

100 Times - 10 Advanced Runes - 10%

200 Times - 20 Advanced Runes - 10%

500 Times - 35 Advanced Runes - 7%

at 200 times,you are just pulling 100 more from the 100 mark to get 20 runes, so it is a 20% rebate. your *ulative math for this event is wrong. same for 50>100