User blog comment:Hamengeri/Project Fyrone: Sta'Drew, Heart of Kumungu/@comment-10256611-20131224135023/@comment-7481207-20131225204215

"Second 2: First slow had decayed to 8%, but Sta'Drew used whipping liane, slowing Ashe by 18%. 8%+18%=26% Second 3: Ashe isn't rooted, because Entanglement can't affect her (cooldown). First slow decayed to 4%, second slow decayed to 12%. 12%+4%=16%."

These calculations are both incorrect. When two slows are on the same champion, each slow except the largest is reduced by about 2 thirds. The slows also stacks multiplicatively, not additively.

In the two examples, the slows would be 21% in the first example and 14% in the second.