Hello everyone! This is my first guide for any champion so I hope it is good! Riven is a very fun champion to play because she can burst down a lot of squishy champions and damage the entire enemy team in team fights if use correctly.

Greater Mark of Desolation x9
Greater Seal of Might x9
Greater Glyph of Vigor x9
Great Quintessence of Desolation x3
I don't really have any rune preferences though I do like the Armor Pen marks and quints. They're nothing specific so they can be changed accordingly to your play style. I don't even own these runes, I just think they would synergize well with Riven's skills.

I take a 21/6/3 path, picking up Havoc in Offense, both +6 stats in Defense, and reduced time spent dead in Utility. I originally wanted to go 21/0/9, but I think that the added armor and MR are better. The Masteries I chose may seem a little odd, but i think that Riven can sustain well while doing large amounts of burst damage with these Masteries.

After testing many items, I came up with this build. I start with Regrowth Pendant and 1 Health Potion because ranged champions can easily harass Riven without any danger. At level 6, I blue pill and buy Boots of Speed and a Vampiric Scepter, maybe picking up a Null-Magic Mantle if I got kills. I get life steal for better laning and so you can heal more and not have to recall as much. Later on I get Mercury's Treads to counter all of the nasty CC that screws Riven over. Phage is a must on Riven. It gives her additional health, attack damage, and a nifty slow that can help her chase enemies with her combos. I get the Brutalizer next for more damage and armor penetration and some CDR to boot. Once you have this inventory full of unfinished items, it's time to build for Warmog's Armor. Warmog's gives you tons of health and regen, which will help immensely once you buy Atma's Impaler. I grab a Frozen Mallet before Atma's because I want to constantly be slowing people so they can't escape my attacks. Once you get Atma's your attack damage will skyrocket. It's just that awesome. Bloodthirster is for even more AD and so much healing that you heal more health than the enemy attacks take away. I finish it off with Youmuu's Ghostblade for the nice active and stats.

I usually try to max Broken Wings first to have a good amount of burst damage. After that I max out Ki Burst for the extra damage in between my Broken Wings attacks. I max Valor last because it isn't all that great, it is a gap closer albeit a small one. It would be amazing if it could go through walls but I make do. Of courrse, get Blade of the xile whenever possible. I think that's a given.

I take Exhaust and Flash usually so I can chase single enemies or escape from ganks. Ghost is also viable to chase enemies as well. I don't really even consider taking anything else.

Overall, Riven is a great champion in my opinion. Once you have Warmog's, enemies will have a lot of difficulty bringing you down. And once you get Atma's you will basically just be stomping them into the ground with your burst damage. If you can get fed early on you will be an unstoppable dunking machine. Good Luck!