Yasuo and Essence Reaver
So while I typically don't post on the boards or like to complain. I discovered something in a game that caught my attention as being a bit overpowered. I wanted to play Yasuo in a game to see if he was as broken as people were saying he was, I'm not a Yasuo main by any means, and I noticed that if you build Static Shiv on him as well as Essence Reaver he reaches 100% crit chance and 40% CDR. While this may not be bad in and of itself. At max rank his ult is on a 16 second cooldown. I was able to use it twice in one team fight. And I thought Lux had a low cooldown on her ult. :P Anyway, just thought I'd point that out.
TLDR:
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On a side note it'd be nice if mages had more options for CDR since it's so easy for AD's to get it now.
Edit: It was pointed out in the comments that with those two items you only reach 30% CDR. I build IE and Death's Dance that game as well. I'm not sure how well either of those items synergize with him though.