Welcome to Fubull's guide about Sivir The Battle Mistress.

This guide aint finish yet, but it will cover the basics, more dept will come later. Cheers.
First of all there are some words in this guide you need to know what means:
Skillsteal = Spell shield. Yes, Sivir is stealing enemy skills, and converting it to mana.
AS = Attackspeed
MP = Magic Penetration
ARP = Armor penetration
AD = Attack Damage


Let me represent this champion:

Sivir is an ranked champion with a standard 400 range. That means you have to be carefull in fights, because you need to come up close.
She have a strong nuke abillity, aoe skill, can absorb spells and boost the whole team with attackspeed and movement.

Sivir is somewhat situational. With this build, you can go something like 15 / 2 / 20, or more. If its noob teams you can go higer. I once scored a quadrakill with them bounching blades once lol.
But again, she is situatinal, you dont nessecary need a godlike team, because Sivir works exelent as a carry. I sometimes semi initiate with Sivir because of her Skillsteal, wich can provoke enemy champs to far ahead to you team.

In this guide, I will try to explain my playstyle, wich pwns, why I picked these items etc etc.

GOOD things:

Very fun champion.
2 great harraser abillities.
Very FUN and GOOD boomerang skill, can be used in many ways, fun kills, nuking, suprise attacks.
Awesome teamplayer.
Huge AOE dps in teamfights.
You will never be 100 % perfect at playing her, means you can always get better.
Strong pusher, can outlast almost any lane.
Turret smasher with ultimate.

.

BAD things:

Not able to take everyone out like: Trynd, JAX, olaf somethimes, most tanks, other high melee dps'er.
Avoidable nuke.
Require timing.
1 escape mechanism, wich you shouldt reiley on.
Often focused on.

Red Runes:
9 x Greater mark of desolation = 15 ARP

Quints:
3 x Greater Quintessence of desolation = 10 ARP

Yellow runes:
9 x Greater Seal of avoidance = 6,8 % dogde

Blue runes:
9 x Greater glyph of intellect = 101 mana

Giving total:
25 ARP, 6,8 % dodge and 101 mana.

The quints and red runes gives you alot of dps increase trough all the game.
The yellow is great combined with her passive wich gives 10/15/20/25 % dodge on move, and makes nimbleness pop you 10 % movement speed frequent.
The blue runes gives you a nice manapool to start with, making sure you dont need to go back early and combined with skillsteal you can stay forever.

Offense

I don't care about the crit, both the crit dmg boost, and the early crit in top of mastery.
If I would rely or even think about the possibillity of crit would improve my combat, it need to atleast be 30-40 % crit in the build. And I don't stack any crit in this item build, so no point getting any crit related masteries.

The first AP in mastery, helps your boomerang blade abit anyway.
15 % spellpen, helps you boomerang.
Actually everything in the offense tree boost your boomerang, except the ARP and attackspeed.

So the skills in offense kinda explains it self, it boost my autoattacks, summoner spells, and abillites.


Defense

Down getting nimbleness because it just rocks. Get the extra armor, because you should be able to absorb alot of spelldmg with skillsteal.


Utility

Man.. I rly hunger for the teleport improvement, but i choose to go defence and offence tree. But than again, exhaust and ignite makes her a killing machine too though.

Start off with a meki pendantand 2 hp pots, it should give you a nice start, and help you keep in lane or mid.

The Boots:
There is alot of good boots in the game, and they are all good for different situations.
Often I take.
The berserker greaves gives you the AS you will need for rest of the game.


Next item would be, now you can start do some good damage with boomerang blade and you don't need to pay much attention too your manapool.


The Page!. With that, you can start hunting sorry victims, who moved to far ahead. and you will get a nice healthpool to start with.


You got all the neccesary stats that can take you along the early / mid game. Decent healthpool, manapool, a slow, and good nuking potential. Combine those with ignite and exhaust, you can shutdown almost any1.


Time for..!
Keep pushing your lane, maybe join on for some ganks, and farm to. It will keep you up-to-date with raw dmgoutput.
Sometimes i actually start with, it helps you to stay in lane early, and gives you the freedom to play a little cocky, and then lifesteal after you have taken som damage. You can stay in lane longer by that.


You are doing excellent damage now, your boomerang is a pain for sqirsy's, and tanks are not very happy for it aswell. Time for some utility!

OR.

The glacial wall is sooo nice to get, its cheap, give you mana (more dmg), and the cooldown reduc is awesome. Take it to counter AD targets. If there is 2+ AD targets, go for glacial wall.

Take banshee wall for heavy AP teams. It will take you a little longer to complete, but heavy AP teams also means sqirsy's, so wont be a prob.


Go for a second[/img]. Again, keeps you up to speed.


Now complete you, you have now 100% slow on enemies, improved hp pool to make you durable.


Complete younow and keep in mind that you will lose you bloodthirster dmg stacks if you die. Also keep farming until you stacks are filled.


Last thing is to complete your.


Conclusion:

You are pretty much awesome now.
your boomerang blade is deadly!, you autoattacks hits 200-300+, and nonetheless, you spellshield can be activated each 6 seconds with frozen hearth! If you went for banshee, you got banshee AND spellshield, wich makes you un-nukeable for a spellcaster 1vs1.

So.. Why dont I get some more AS?. well you dont need it. And if you start working on AS, you boomerang will be useless mid/lategame. Forces you to take more chances with you autoattacks.