Hey guys, CosmoPotato here with my a champion guide, featuring Sivir.

I have been an AD Carry main for since I began playing LoL. Since the beginning, I always enjoyed playing Sivir because of her Spell Shield and Ultimate.

Anyways, hope you like & learn something from my guide :).

Statistics
Example Stat: At Lvl 1 (+increase per Lvl)
Health: 515.76 (+82)
Health Regen: 5.17 (+0.55)
Mana: 284 (+50)
Mana Regen: 8.01 (+0.9)
Range: 500
Attack Damage: 52.04 (+3)
Attack Speed: 0.658 (+1.6%)
Armor: 22.21 (+3.25)
Magic Resist: 30 (+0)
Movement Speed: 335

Abilities
Example Ability
Description.
Cooldown: XXX
Mana Cost: XXX
Range: XXX

Fleet of Foot (Passive)
Sivir gains 30 / 35 / 40 / 45 / 50 movement speed at Levels 1 / 6 / 11 / 16 / 18 for 2 seconds when she hits an enemy champion with her abilities or basic attacks.
Cooldown: N/A
Mana Cost: N/A
Range: N/A

Boomerang Blade (Q)
ACTIVE: Sivir hurls her crossblade to a target location, which then returns to her. Enemies in its path take 25 / 45 / 65 / 85 / 105 (+ 70 / 80 / 90 / 100 / 110% AD) (+ 50% AP) physical damage, with 15% reduced damage to each subsequent target, down to a minimum of 40%.
Cooldown: 9
Mana Cost: 70 / 80 / 90 / 100 / 110
Range: 1250

Ricochet (W)
ACTIVE: Sivir's next 3 basic attacks bounce to nearby enemies, dealing 50 / 55 / 60 / 65 / 70% AD to each additional enemy hit. Only the first target is affected by on-hit effects.
Cooldown: 9 / 8 / 7 / 6 / 5
Mana Cost: 60
Range: N/A

Spell Shield (E)
ACTIVE: Sivir creates a magical barrier that lasts up to 1.5 seconds, blocking the next enemy ability used on Sivir. If an ability is blocked by this sheild, Sivir gains 80 / 95 / 110 / 125 / 140 mana.
Cooldown: 22 / 19 / 16 / 13 / 10
Mana Cost: 0
Range: N/A

On the Hunt (R)
PASSIVE: Sivir gains 40 / 60 / 80% attack speed while Ricochet is active.

ACTIVE: Sivir rallies her allies for 8 seconds, granting all nearby allies an initial 60% movement Speed bonus that reduces to 20% after a 2 / 3 / 4 seconds.
Cooldown: 120 / 100 / 80
Mana Cost: 100
Range: 1000

Pros
+ Great Waveclear with Q and W.
+ Relevant all game long.
+ Great for team fighting with Ultimate.
+ Very useful ability in spell sheildSpell Shield.
+ Passive gives strong kiting potential.

Cons
- Early mana issues.
- No reliable gap closer, such as Tristana's Rocket Jump or Graves's Quickdraw.
- Does purely physical damage.
- Squishy and susceptible to hard Crowd Control.

These runes are standard for AD Carries. 9 AD Marks to maximize damage output, period. As an AD Carry, your job is to provide as much DPS as possible. 9 Armor Seals and 9 MR Glyphs to provide defensive stats most efficiently.

For Quintessences, there are many options. I prefer Quints of Attack Speed as they scale better into late-game. Other viable options include AD to boost your early game or Lifesteal to sustain in lane.

For Masteries I take the standard 21/9/0.

The 21 in Offense will ensure maximum damage output as an AD Carry. This setup will give you the necessary AD, Armor Penetration, and some sustain in lane from Feast. Alternatively, you can swap out a point in Warlord for Spell Weaving depending on your playstyle.

The 9 in Defense are a must, as they provide very beneficial stats for the laning phase. Generally, this is the only page that should be taken.

Of course, we want to take On the Hunt whenever possible, at levels 6, 11, and 16.

Other than that, we want to max our Q first due to the extra damage it provides at each level.

Next, we want to prioritize W for increased waveclear and reduced cooldown.

Lastly, we would level our E because the extra mana and less cooldown is not as necessary as our other abilities. If you can time your Spell Shield correctly, rank 1 should be fine throughout the whole game.

Early Ability Order
At level 1, you want to take W most of the time. This would help with trades as this ability acts as an auto-attack reset, but more importantly, it is for pushing the first wave. This well help you reach level 2 first.

At level 2, I personally prefer taking E, but it really depends on the matchup. If you want to play aggressive (maybe you hit level 2 first), then getting Q is the way to go.

Starting Items

As usual, with any AD Carry, you want to start with Doran's Blade for the AD, Lifesteal, and Health. Also pick up a Health Potion for sustain and the standard Trinket.

First Back

On your first back, you should be aiming for a B.F. Sword. The 50 AD it provides is enormous, and should let you win trades, assuming the enemy AD Carry did not have the money for one. In general, just try to increase your AD every time you recall. If you can only afford a Long Sword, then buy one.

If you are behind or doing poorly in lane, picking up an Avarice Blade is not a bad idea. It provides the gold income to help you get back in the game, and is a component for your Statikk Shiv anyways.

Core Items

Infinity Edge is a must on Sivir. The 80 Attack Damage, the Crit Chance, and bonus Critical Damage are all very good on AD Carries. This will help you provide sustained DPS in early teamfights.

Berserker's Greaves are the best option for most AD Carries, as it provides some Attack Speed. Since Tier 2 boots are usually a must-get, this item is essential as there are no better options.

Statikk Shiv is a great item on Sivir for many reasons. She really could use the 100 bonus magic damages against armor-stacking teams. Also, it synergizes well with Infinity Edge due to the Crit Chance. Extra Attack Speed is always a good thing, too. However, late game, the passive of Statikk Shiv starts to fall off, and I generally sell mine for a Phantom Dancer for the better stats.

Last Whisper is a must-buy after Statikk Shiv. It gives you the greatly needed Armor Penetration in order to shred through tanks. Alternatively, you can buy other Armor bypassing items, such as Youmuu's Ghostblade or Blade of the Ruined King, but from my experience, Last Whisper is the best option.

Scrying Orb is definitely the best late-game option for AD Carries, such as Sivir. Usually, you want to have Scrying Orb by the end of the laning phase, around the 15 minute mark. Reasons + Great for checking Dragon/Baron from a safe distance. + Scout nearby brushes for enemies. + Sets up your auto-attacks. You cannot auto-attack an enemy who is not in sight.

Situational

The Lifesteal on this item is insane. Though you will buy this 99% of the time, it can be omitted depending on the enemy team composition.

Always buy a Quicksilver Sash against Crowd Control heavy teams, as the cleanse could be the difference between a won and lost teamfight. Late-game, build this item into Mercurial Scimitar as there is no reason not to.

By a Guardian Angel when both Armor and Magic Resist are needed or when you are the most important member on the team. The revive has the potential to turn the game around.

This item is for Physical Damage heavy teams. The passive of Randuin's Omen is still very useful, even if you aren't stacking Armor and Magic Resist.

Banshee's Veil is a good all-around item. Especially useful against Magic Damage compositions, the extra Spell Shield and Health Regeneration will increase your survivability.

Not much explanation here. Just buy it when you have nothing else to spend your gold on.

Overall, Sivir is a strong laner when she is used correctly.

Level 1
At Level 1, try to gain the experience advantage so you can hit Level 2 first. If your Jungler is starting on the other side and you trust your support, starting Krugs on blue side and Gromp on red side is a good idea.

If you start in lane, use Ricochet to push the wave.

Level 2
If the matchup is favorable, feel free to play aggressive if you hit Level 2 first. Level Q first and try to cripple your opponents.

Otherwise, take E and play this lane like any other (unless specified in Champion Matchups).

Level 3 - Level 5
During this time, make sure you / your support are warding and watching for ganks. With Sivir's low mobility, sometimes one Spell Shield isn't enough. With proper vision control, you can easily push up to their tower and deny the enemy AD Carry farm. If there is sub-adequate vision, it would be better off to keep the wave in the middle or on your side of the lane.

At these levels, Sivir trades really well. Using her AA- W-AA combo, she can get off two attacks in the time of one, due to the AA reset. You can follow up with a Q for a bit more damage, but be careful about the mama cost. Use Spell Shield to keep yourself as healthy as possible.

Level 6+
This is when Sivir gets her mobility (her Ult). Using this, you can get yourself out of sticky situations unless the enemy has hard CC. On the Hunt is also really good for chasing down enemies who are low on health.

This is where Sivir really shines. Her Ultimate is arguably made for teamfighting, granting your whole team incredible chasing potential and mobility.

During teamfights, your job as an AD Carry is to output as much DPS as possible. As Sivir, you have decent AOE in Ricochet and great protection from Spell Shield. Always pay attention to possible abilities that you can block.

One of Sivir's biggest weaknesses is her range. Due to this, she requires really good positioning to do her job properly. Always stay behind your front line, stutter-step, and kite back if you have to.

That's it :). If you liked my guide of found it helpful, an upvote would be much appreciated. As always, I am open to any constructive criticism to help improve this guide. Best of wishes on the Rift.

~ CosmoPotato

Also, artwork for this guide, such as banners or pictures, would be much appreciated. Thanks in advance & I will be sure to cite your work.

6 / 27 / 2015: Added Scrying Orb to "Items". (Recommended by Hopesedge.)
6 / 23 / 2015: Added "Teamfighting".
6 / 16 / 2015: Added "Items".
6 / 16 / 2015: Added Sivir's abilities under "All About Sivir".
6 / 16 / 2015: Added "Laning With Sivir".
6 / 11 / 2015: Published Guide.