Thread:FingersMeller/@comment-11200708-20181227011521

https://leagueoflegends.wikia.com/wiki/Template:Item_data_Mikael%27s_Crucible?curid=1220198&diff=2763712&oldid=2762254

It's 20% as of this patch. Check the patch notes https://euw.leagueoflegends.com/en/news/game-updates/patch/patch-824b-notes 