Why pick Riven? CUS SHES OP AS FUCK!
Her passive is what makes her OP in the top lane, and the 3 minidash q's, miniaoestun w, and SHEILD+Dash e along with her R that gives her FREE AD with a executioner cone ultimate. Best of all, she doesnt have mana or energy so you can spam all of that over and over again. SHE CAN trade every 5-10 seconds for ~300 dmg at lvl 5...
PS: Her q scales 3 times with ad...(OP)

It's okay to land some early skill points into your E(sheild) if your losing trades and losing lane. It can help you farm, and thats what you need mostly.

you can swap out the ad for armor pen, but it the endgame your going to get a Last Whisper so i wouldn't recommend it.

YOU CAN jungle riven. similar to lee sin jungle, Either smite/flash or smite/exhaust. Get q, start red and gank top/mid/bot. you have 4 dashes and a stun at lvl 3.. use it. GANK GANK GANK. she can snowball fast midgame.

Best chance is to go for their carry/squishy ap. You do insane burst with your R on. follow in with q -> flash auto-> q auto-> w auto -> shield into them while they are running so your close to them. Use r again to pick up kills.

Why choose these masteries. Riven scales with AD so ofc you would go 21 in the offense tree. Why not pick up the crit mastery, because YOU DONT BUILD CRIT ON RIVEN!@!@!. Please never build atma's or triforce on riven. Why pick up the regen and reduced minion dmg? Well theres a neat little trick. All you do is take wraiths of your opponent or your jungler, you can ask mid for help or just tank em, you might have to waste 1 hp pot but its worth it.

Don't pick riven into Vladimir, if he is equal skill level or better than you, you'll lose 100% of the time. Same thing for Irelia and Garen and sometimes Olaf.
FARM FARM FARM. I usually hit 200 cs by 25 minutes, you should shoot for around that. Riven needs items to do good, so farm to get them.
NEVER BUILD WARMOGS OR TRIFORCE OR CRIT items... you get more survivability with GA/maw. More ad you stack, more your shield will shield you for :D.

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