New BotRK is great! Theorycrafting and experiences so far.
So I theorized about the new BotRK quite a while now and how it's going to be much better on a lot of champions after the changes but now I actually got to see it in action on two champions in particular - 
and 
.
I had the plasure of testing it myself on Yi. Previously, Yi always had the problem that he would overcap attack speed in the late game on top of him having an abundance of attack speed from Highlander and Bloodrazor in the early game, yet not a lot of AD to make it worth while. Some people have been testing Warrior but you just need to make a DPS calc to see that it really isn't all that efficient on Yi before the overcap problem comes into play. This overcapping problem was present on both the crit and the on-hit build, but especially on the on-hit build.
Then there's also the fact that the bonus life steal and AD it now has synergizes really well with further crit items so that it might be a bigger contender for the on-hit build, which is currently considered the best build on Master Yi. After testing it ( even though I accidently took Deathfire Touch ) I can safely say that the crit build can now hold up with the on-hit build because of the BotRK changes alone. You can basically make the choice whether you want to go for on-hit and be better at shredding tanks or going for crit which will alow you to be better at bursting and assassinating squishies, having that option is pretty neat.
Next up it's Lucian. Alongside the buffs to his cast times he got anyway, with the Fervor Buff of last patch and now the BotRK that is much more stat efficient and gives more life steal and AD, I figured that rushing it on Lucian would be a great idea. Let me explain.
Last patch, one of the biggest problems Lucian had in my opinion was itemization. He could either choose to rush Essence Reaver which is rather weak early on and would mean that he couldn't capitalize on his early game strength as much or he would go for a semi-lethality build, which ultimately would make his already relatively bad late game even worse.
Rushing the new BotRK on him seemed like a good idea to me - traditionally, it has always been a great early game pickup, combine that with the fact that Lucian is generally considered an early game champion, that BotRK got more stat efficient overall and that Lucian can make infinitely more use of its buffed AD than the attack speed boost and combined with the fact that it makes for a really clean transition into crit items like Essence Reaver Rapidfire Cannon, it just makes for a really neat buff for Lucian, alongside the buffs he already got. The math behind it seemed to fit aswell, so in theory it's pretty great.
Since I'm not an adc player myself though I thought that I wouldn't be able to test it at first. Luckily, I was autofilling and convinced my adc to test it for me and he did. After seeing it in action I can safely say that all of the above is true - it really is a great rush on Lucian combined with Fervor and transitioning into Essence Reaver Crit - the big problem though is his mana, since he will get Essence Reaver a bit later. It wasn't a huge factor and it won't make Essence Reaver a better rush compared to BotRK, yet it could get problematic in lanes where he is forced to use his abilities to counter-push his enemies or when the enemy will be extremely hard to force into a duel or to poke down - I'd argue that if that is the case, you shouldn't have picked Lucian in the first place.
What I can ultimately conclude from this though is that BotRK finally has hit its sweet spot. I can already say that it's great on Lucian and Yi, but in theory it should also be a straight out buff to Ezreal who loves the stat shift extremely much and didn't use the extra effects of the active all that much anyway compared to others, or to Varus who after the Lethality and Deathfire nerfs will make extremely good use of a Fervor BotRK rush crit build, like some people do already. Anyway, here are some build examples for the new BotRK that I think are going to be really good.
:
Crit: 
or 
or 
or 
or 
On-HIt: 
or or 
Masteries: 18/12/0 with Fervor of Battle, on both builds.
Standard attack speed rune page: AS Quints, AD Marks, Armor Seals, MRperlvl Glyphs.
:
or or or or 
Masteries: 18/12/0 with Fervor of Battle.
Runes can have several configurations, you definitely need to have 10% CDR to cap out though. You can either trade some flat MR or MRperlvl Glyphs for 6 scaling CDR Glyphs, or what I've been trying, 3 Flat CDR Quints and 3 flat CDR Glyphs with AD marks, which has working out for me pretty swell on a lot of champions even though I've never seen it on Lucian.
:
Nothing has changed, same build as always just that BotRK got buffed for him. New Warlord's might be pretty good since because of his Q and Sheen proccing life steal he is a really good user of it if he times it correctly - on the other hand, he is also a really good Fervor stacker with his Q and attack speed bonuses. You'd have to test both and see which is better for yourself.
:
With his Q Mechanic changed to force you to be more auto attack reliant, the passive change from way back, the Deathfire nerf and the Lethality nerfs from last patch plus the BotRK buffs for AD and crit champions in general means that crit with BotRK is most likely better than lethality in every case. The question is, do you want to rush BotRK on him too ( math-wise it's still pretty good on him but not nearly as good as on Lucian ) or do you want to go for the classic Essence Reaver build and pick it up later.
Essence Reaver Rush: 
or or or or
18/12/0 every time. Since this build has less AD, Deathfire was nerfed and all the reasons I've mentioned above, I think it will most likely be outclassed by Fervor and Warlord's now. Warlord's will probably be better if you go for the Essence Reaver rush since you will be lacking life steal and lane sustain early on, whereas with a BotRK rush you will have both and you would rather have the extra damage from Fervor.
Rune configuration is the same as Lucian, don't forget that 10%!
Since I'm running out of time, I figured I might list the other BotRK users who I don't consider to synergize as strong as the above in more shorter paragraphs. Sorry about that.
: Often seen in combination with Lulu to receive those sweet sweet on-hit and attack speed buffs, Kog'Maw also has a huge attack speed overcap problem, even moreso than Yi does. With the new BotRK it will be less of a problem and he might just consider skipping Guinsoo's for further crit if Lulu is not around to buff him, since the new BotRK became much more efficient in crit builds.
: On the reworked version it definitely seems to be the staple item alongside Titanic Hydra into tank. Since he never had overcap problems and since he doesn't life steal as much because his overall auto attack damage is lower since he's not a carry but a bruiser, BotRK is not as much of a buff as it is on other champions. Overall it stayed the same for him most likely with only a mariginal difference in overall power.
: Some Irelias have already been seen picking up BotRK some time later into the game but I think now it has gotten better. Yes, she liked attack speed more than the AD and never had an overcap problem, but the fact that the item got more stat efficient in general and that all the AD and life steal synergizes really well with her Q and Sheen procs, she will probably heal much more than she did previosuly with a BotRK pickup on top of having more burst, though her DPS might have gone down slightly or stayed the same. Overall a buff and a neat item to consider after your core.
: Most Tryn players already rush it and it basically has just gotten better to the point where it might just be the mandatory rush. More overall stat efficiency, life steal and AD mean much better synergy with his naturally high base stats and extra crit chance on top of it going down by 100 in cost, making it accessable more early. Not much else to say here.
: Now this is an interesting case. Since Yasuo only wants attack speed as long as it benefits his Q CD since after that, raw AD is just much more efficient on him, he never really considered BotRK since he would overcap his Q CDR cap with it, on top of BT giving him that sweet shield, double the life steal and the fact that he shreds rather well through tanks already. Now that it won't overcap his Q CDR cap anymore, has more AD and life steal, that nice extra on-hit and is generally cheaper than BT, it is now a dangerous contender to its throne. Ultimately, it will be a situational decision - BT for more total tankiness and heals plus more burst against squishies, BotRK for extra DPS, stickyness and cheap extra percentage on-hit against bruisers and tanks.
Now there are probably a lot more out there but I'd call this bunch the major users of it now that it got changed. Tell me if I forgot someone and I might talk about it if I ever find the time to. Hope you liked reading it all!
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