Hello, I am MechaHunter, a Rengar and Riven player, I've climbed quite a lot with riven mid in Season 7, I am currently mostly playing Flex Queue and waiting for the next season to start to continue my climb.

Riven mid got me out of silver, I hope it will help you too.

Disclaimer: I am just a gold 5 player who is trying to help anyone who likes playing Riven but cannot find success with her.

This is my first guide, hope it's helpful!

Arcane Comet
This keystone has synergy with your Q Broken Wings, and your W Ki Burst, your Q making it come off cooldown when you used it, and W easily procs it.
I choose Gathering Storm for the practically infinite scaling, and Stopwatch for outplaying, I also take Cosmic Insight for the cdr cap

ALTERNATIVES
Electrocute Can be ran for quick trades, also for the Lethality increase from Sudden Impact, Cheap Shot for the bonus true damage for stunning someone with your Ki Burst, Eyeball Collection For bonus AD from kills and ward takedowns, and then Ravenous Hunter for the bonus lifesteal.

You can also take Second Wind in your secondary tree if you're in a poke lane, combined with Doran's Shield it provides nice sustain.

Summon Aery
Now this, this rune is my favorite run if you want to just straight up bully the enemy.

Youmuu's Ghostblade gives you a lot of out of combat movement speed, making you effective at roaming, it also provides lethality and CDR which is always good.

Black Cleaver Makes you a tad bit tankier, and allows you to negate quite a lot of armor paired with Duskblade of Draktharr And it also gives you 20 percent CDR. Duskblade of Draktharr Gives you a ton of burst potential, you've probably seen lethality Riven oneshot montages, and that's all because of this item, core item on lethality Riven. Lord Dominik's Regards Pairs well with this build. since it gives armor penetration, more damage against tankier champions than you, it mostly makes shredding tanks easier. Adaptive Helm Is an item that some of you might consider questionable, but it is good against Cassiopeia, Kog'Maw(Because of his W, and sometimes R), and Karthus, because of this passive: Taking magic damage from a spell or effect reduces all subsequent magic damage taken from that spell or effect by 20% for 4 seconds. Randuin's Omen is good against autoattack/crit champions like : Yasuo, Master Yi, Tryndamere, and basically all ADC's, combined with Adaptive Helm it's really effective against a fed Kog'Maw.

Flash Please always take this, it is the core spell for almost every champion, it also allows you to make "flashy" plays :P.

Ignite Basically kill pressure, snowball potential.

Barrier I don't see Riven players run this, honestly I don't recommend taking it because it won't help you with snowballing.

Exhaust I don't recommend taking this because it doesn't provide as much kill pressure as ignite.

Teleport Please don't.

Cleanse You shouldn't take this BUT, if their jungler is rammus or shen, and their Midlaner Ekko, or other champions with heavy CC.

Before your teammates start flaming you, ban your Riven or just straight up dodge, just tell them that you're gonna carry them and instalock her, link op.gg if needed :P

PROS
-High mobility
-high snowball potential
-high skill cap
-fun to master
-burst
CONS
-Hard to master
-Squishy
-Weak to poke
-Useless if put behind
-Predictable
-No built-in sustain
-Glass cannon with this build

Don't let the number of cons deter you, a good Riven player can play around all of them. And this guide is dedicated to add onto your knowledge of her, and how good you are with her.

You should pick off squishies before the fight, if you have Randuin's Omen or another Bruiser/tank item go in with your tank, try to stun and knockup as many people as you can, finish people off with your ultimate, you are a glass cannon with this build, so if you don't buy any tank items you might get CC locked and just straight up oneshot if you're not careful

If you are struggling with farming, use your Q as an autoattack buff, and if you are in a poke lane, farm under turret, or use your Q and W to farm.

Thank you for viewing my Lethality Riven guide, please leave a comment, upvote, and if you have any criticism or arguments be sure to comment that also.I know that this guide looks very awful but it's my first one and I hope you don't mind it!