Riven, the Exile, although extremely new, has proven to be a fantastic champion. People may say that she is underpowered, others may say otherwise, but in my opinion she has been one of the better champions that have been recently released. I hope that if you read my guide you'll be inspired to try a different build for Riven, or use this build when she is in the free champion rotation if you do not own her. The best aspect of Riven is she is amazingly fun to play, so when you do try her, I hope you learn this and appreciate how awesome this champion really is.

Pros:
Cooldown Champion
Easily Abuses
Can Escape and Chase Efficiently
Fun

Cons:
Vulnerable to Crowd Control
Easily Abused

Flash is an amazing Summoner Spell. It makes chasing, tower diving and retreating so much more easier. It is one of the most commonly used Summoner Spells, and for a reason too.

Exhaust can easily get you a much wanted first blood. It's simply amazing throughout the whole game too, so use it constantly.

These are pretty simple. I would have taken 21/9/0 if Strength of Spirit wasn't completely useless on Riven, so Good Hands are in place of the extra three masteries on the Defense tree.

Greater Mark of Desolation - Armor Penetration is extremely useful on Riven, as all of her damaging abilities deal physical damage.

Greater Seal of Armor - Riven doesn't have the best armor values, so these can easily help you in the early laning phase.

Greater Glyph of Magic Resist - These are also here for survivabilty, and prove very useful in the early laning phase.

Greater Quintessence of Health - These are my default Quintessences for any champion I play, and Riven works exceptionally well with them. Obviously you can choose Greater Quintessence of Movement Speed if you like them, but these ones are my number one choice.

Doran's Blade - 100 extra health, 10 extra attack damage and 3% Lifesteal. This is straight foward. If you feel you would rather go straight into the build and get a Long Sword and Health Potion instead, go ahead, although I prefer Doran's Blade.

Boots Obviously, and another choice for your starting item along with 3x Health Potion.

The Brutalizer - Another straight foward item in this build. Cooldown Reduction alongside a Cooldown champion works wonders, and the extra damage increases your abilities effectiveness. Yes please.

Vampiric Scepter - Bloodthirster comes relatively late in the build, so having some lifesteal in the mean time is nice.

Mercury's Treads - These boots are needed for Riven to play well in a team fight. Crowd Control kills her, and the added Magic Resist is amazing.

Frozen Mallet - Valor, basic attack, Ki Burst, basic attack is a common combiantion for me. With those basic attacks dealing an additional slow, it makes the combo much smoother, and awesomer. And of course the amazing bonus health doesn't hurt.

Atma's Impaler - I love this item. Added armor, critical strike and masses of attack damage at later levels, this is amazing in combination with the awesomness of Riven herself.

Bloodthirster - This is another amazing item for Riven, and if you know how to escape well with Broken Wings, Valor and Flash, hopefully you can constantly keep up those stacks.

Banshee's Veil - This item has proven to be amazing over and over again. Use it.

Youmuu's Ghostblade - Remember The Brutalizer you got way back. Now it's time to make it...a LEGENDARY ITEM ''SPARKLES''.

Broken Wings - I get one point in this third level, because of the amazing combos that can be achieved with it early game. Then I forget about it for a long, long time, because I find it's her least useful ability, although still quite amazing.

Ki Burst - It's large amounts of damage, as well as an amazing stun can really help you kill champions, although I feel Valor just a tad better.

Valor - This is an awesome poking tool, as well as awesome protection that scales in awesome amounts with your awesome attack damage.

Blade of the Exile - Obviously you'll get this whenver you can, with a relatively short cooldown, fairly long duration, and amzing bonus stats, this spell can prove time and time again.

Wind Slash - This is Riven's only ranged ability, so it should be used carefully and mostly to chase enemy champions down.

This guide is obviously unfinished, I just wanted to give people an alternative build to Riven to hopefully experiment whenever they can. Feedback will be appreciated :)