Yes yes, this is a guide for the amazing battle mistress, Sivir. Please leave any comments at the end, and please actually try out the build before commenting, yes, I know that some item choices are questionable, but please try them before bashing them. Thank you! ^-^

So I went 21/9/0

First I want to go over why I chose the masteries that I did. This is not a typical Sivir Masteries setup, seeing as how I ignored utility altogether, and focused mostly on offense. The reason I did this, is because Sivir excels in her offensive capabilities. I went enough into defense to snag the dodge bonuses, given that she can dodge when she's running away. But I've found when boosting her offense like this, she is invaluable in team fights.

Pros:
+Great farmer
+Lots of damage
+Lots of speed
+Excellent range
+Spell shield
+Tears it up in team fights

Cons:
-Very squishy
-Teams will target you
-You are sometimes blamed for lost team fights
-Mana can be an issue

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You're probably asking yourself why I have two phantom dancers in there. Well, the reason is because with two phantom dancers, Sivir gets a huge boost to movement speed, crit, and attack speed. These attributes, combined with the damage from the infinity edge, and the bloodthirster, will make you a force to be reckoned with.


: These are great shoes for Sivir, they boost her AS, which she'll need a lot of. These are a must-have.
: I don't think I have to explain how amazing this weapon is. It gains bonuses every time you get a kill, and it will add a nice chunk of AD as well as leech. Definitely a must-have.
: Speaks for itself. As I said before, adds a nice AS, Crit, and Movement Speed boost. This item isn't really set in stone for this slot, you can always grab an infinity edge first if you feel like you need the damage. However, I feel like the dancer will give you the speed you need, and combined with the bloodthirster, you'll be healing yourself often.
: Always a staple item for every AD carry. You'll never be disappointed with it. Adds some nice AD and crit damage.
: A second phantom dancer is my questionable add to this Sivir build. However, I've found that Sivir NEEDS the extra AS and crit and movement speed. She's squishy, so the faster, the better. If you're not doing too hot, you can always grab a Frozen Mallet or something to boost your HP a bit.
: This adds a really nice chunk of damage, and also adds more speed. Yes, I know, at some point you might think the speed becomes redundant. But believe me, most of the time you won't even reach this point. But if you do, this will add 4% of their health as damage, and you'll be attacking upwards of ~2.3, which is super fast.

: Increases Sivir's dodge chance by 10/15/20/25% while moving

To be honest, this isn't the GREATEST passive ever. However, it does help you more than you might realize. You can always throw a boomerang blade, all the while running from your opponent, most of the time guaranteeing 2 hits, and you have a chance to dodge whatever they might throw your way.

: Sivir hurls her crossblade like a boomerang dealing 75 / 120 / 165 / 210 / 255 (+75% of ability power) and (+95% of bonus attack damage) magic damage to the first unit and 20% reduced damage to each subsequent target.

You will be using this. A lot. But take care, it will suck the mana right out of you, considering the fact that Sivir doesn't get all that much. Use it wisely. This is a great skill, it can go through walls, and it has the potential to hit twice. It can also go right through minions, and hit a champ, or even multiple champs. This will be your main harassment tool.

: Toggle: Sivir's basic attacks will bounce to 1 / 2 / 3 / 4 / 5 additional target(s), dealing 25% less damage with each bounce (Only the first procs item effects).

Knowing when to toggle this on is a must. You don't want to be wasting your mana for no reason. This is the skill that you will use most in team fights. I say that, because in EVERY team fight, you should have this active. It will bounce and hit all the team members, widdling them down so that you, or your teammates, can pick them off easily. Keep in mind, though, you are extremely squishy. NEVER INITIATE A TEAM FIGHT! EVER!

: Creates a magical barrier which blocks a single enemy ability used on Sivir. Lasts up to 3 seconds.

If an ability is blocked by the shield, Sivir regains 150 mana.

Spell Shield is a wonderful ability, that is basically a banshee's veil that you can use whenever you need it, AND you get mana from it. Use this often to replenish your mana, and strike back at the enemy.

: Grants Sivir and nearby allies 25% movement speed and 25 / 45 / 65% attack speed (half for allies) for 15 seconds.

This ult will help your team in team fights IMMEASURABLY. Use it at the start of a team fight, and your allies will attack a lot faster, and move faster to pick off stragglers. You can also use this to chase, or run away from a battle. Be careful not to waste it.

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Clarity: You are all probably wondering why I shoved clarity in here. The reason, is because Sivir lacks mana. And you will run out quite often. If you need to get an extra boomerang blade in to kill them, you don't want to be out of mana at that exact moment. This is controversial, because clarity isn't used a whole lot. But I would rather use Clarity, than waste gold on getting mana-boosting items. Which, some people might argue you don't need for her anyways. But I think you'll be a lot more content with not running out of mana every 10 seconds.

Flash: Flash is just a must. I use this on almost every character, because it has the best utility in the game. Flash away from an enemy through a wall, or just away, flash TO them and kill them, etc.

Alternatives

Exhaust: Exhaust is always a nice spell. It can slow them down so that you can finish them off and prevent them from running, or slow them down so you can get away.

Ghost: This one is helpful as well. Self-explanatory, just another "move faster" kind of deal. But with Sivir, you'll have the speed to get away.

Early Game

During the first stages, you're going to want to go ahead and grab your Doran's Blade (Or boots and potions, if you would prefer) and move on into your lane. Sivir can take mid very well, and harass better than most with boomerang blade. You can kill minions pretty easily, but familiarize yourself with her auto-attack, so as to last hit minions easier. You don't want to waste your boomerang blade on minions, but hitting the champ will likely pick off some minions, so then, it would be acceptable. If you waste it, you'll wish you hadn't. Your mana will run out. Gank whenever possible, assuming that you're doing fine in mid. Sivir can be sneaky, and throw her blade through a wall, or from/into bushes.

Mid Game

At this point, you should already have the bloodrazor, and possibly the phantom dancer, if not the zeal, at least. Now you can start actively using ricochet to the best of your ability. You'll be attacking fast, and a lot of enemies at once. Continue to be careful with your mana, however, and if a team fight starts up, toggle ricochet on, and use your ult so that your team as the speed advantage. Be very careful, YOU WILL DIE EASILY, so stay near the back and toss your blade and auto-attack often. Target-fire the weakest, and the ricochet will do the rest.

Late Game

Late game always comes down to your choices along the way. You should have your whole core item set by now (exluding madred's, because hopefully you've won by now). Just keep doing what you've been doing. Now, you're a little hardier, given your speed and attack speed with leech. You'll be healing yourself pretty well while attacking, and often, given the speed. Spam your blade now, you should have enough mana to do so, and it might be a good idea to keep ricochet active all the time, just in case.

And there, ladies and gents, is a very Aggressive-type build for Sivir. If you like it, let me know in the comments, and please use the build before commenting and/or voting. If there are any changes you think need to be made, please let me know, and I will consider them.

:D Sivir. Yup.

9/8/11: Switched from Doran's Blade to Boots and potions at startup
9/8/11: Added one game

Here is a game I just played 5 minutes ago. First game after using this build. It's not AMAZING but the game DID end in about 22 minutes, soyah: