Thoughts on Yasuo builds
Prior to the nerf to IE, this was the standard Yasuo build (and probably still is):
There's a lot of flexibility there- BOTRK could be BT, GA could be maw, zerkers could be mercs- but the core of the build is shiv+IE. As a rush item, shiv had a LOT of upside. It gave you real trading potential, good crit chance, decent wave clear, attack speed to reduce your Q CD... basically everything you could want. Until this most recent patch, the full build with 5 marks and 1 seal of crit chance gave him 100% crit chance. However, neither Shiv nor IE were REALLY efficient on Yasuo. His passive gives him 10% reduced crit damage, which made IE only give him 45% bonus crit damage (rather than 50) and Shiv only do 180 magic damage (rather thn 200) on crit. Even so, they were undoubtedly the best items on Yasuo at the time.
With the nerf to IE, Yasuo can no longer gain 100% crit chance from IE+Shiv without dedicating ALL his marks and some of his seals or glyphs to crit chance. Does that merit a change in his build? Hard to say. Dedicating that many of your runes to crit chance makes very little sense, though, so it's at least worth taking a look at builds again. Unless you change the build, I don't think you can afforf to get 100% crit any more. With the removal of Atma's and Executioner's Calling, there are only 5 crit chance items left on Summoner's Rift:

So, let's take a look at some alternate builds.
Build choice 1:
This is the obvious change to still get 100% crit. The Phantom Dancer gives much more attack speed than shiv, and with the help of zerkers will get you enough attack speed to max out the CD on your Q, so the benefits of BOTRK are lessened. It has the benefit of doing a little more burst to squishies than the old build (pretty marginal without the shiv burst), and it also does QUITE a bit more DPS to squishies. You won't need crit chance runes, as the build gives you too much crit already. That inefficiency bothers me a little, but I would get over it... if the build weren't so weak in lane. Without shiv, your early trades are weak, your wave clear is weak... you'll generally have a hard time in lane. Furthermore, your build path is expensive- 300 gold more than the old one for your first two items, and that was already expensive.
Build choice 2:

This is a pretty strange build. Trinity Force, in theory, should be good on Yasuo. He makes some use of all its stats except mana, and should be able to use the sheen portion very well. Its movespeed will also let him run down pretty much anything, even if he somehow couldn't before. However, the build ends up being much more reliant on burst than his old build, and doesn't really have much (if any) more burst than it. It certainly doesn't have the same DPS. Furthermore, Trinity Force is horribly expensive as a first item and doesn't give all that much crit chance on its own. You could perhaps build sheen>phantom dancer>complete trinity force, but I don't see much benefit of any build with TriForce over builds without it (apart from just being happy that you have 100% crit with the same runes as before).
Build choice 3:

This is definitely NOT the old build. Ghostblade+Phantom dancer gives you exactly 100% crit, which is nice, as well as all the attack speed you'll need. Ghostblade will give you some decent damage and trades and increase your early ult damage more than the old build would. It's a LOT cheaper of a 2 item build than before, and is a little more flexible- with your ult and ghostblade, last whisper might even be optional in some games (could be replaced with BT or Maw, even Scimitar). Your late game DPS still likely won't be quite as good, but your mid game spikes should come sooner and Hydra gives a great boost to your burst. You may have some difficulty early- you won't have any crit at all until you get started on your Avarice blade. However, the additional AD you'll be able to get on your marks over the old build should, hopefully, help to deal with this.
I don't think build 1 or 2 are good options. Realistically, the only options are the original build and build 3. Overall, I'd think that the original build is (very, very marginally) better than build 3. But in a situation where you need to be a little more defensive in your build, the 3rd build is much more adaptable to that situation than the old one. The armor pen on that ghostblade is a REALLY big deal when you already have free %bonus pen.
Other people's thoughts?
, and you don't want to risk not getting any crits.
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