STATS

• Base Health Pool

  - 580 HP (+95 per level)

• Base HP Regen

  - 8.5 HP (+ ~1 per level)

• Base Mana Pool

  - 350 (+30 per level)

• Base Mana Regen

  - 8 (+ ~1 per level).

• Attack Range

  - 200 (Does not increase by leveling up)

• Base Attack Damage

  - 63 (+4 per level)

• Base Attack Speed

  - 0.656 (+2.5% per level)

• Base Armor

  - 36 (+3 per level)

• Base Magic Resistance

  - 32 (+ ~1 per level)

• Movement Speed

  - 335 (Does not increase by leveling up)

KIT POWER

• Carry

  4/5

  The higher this is, the more likely this hero can win the game for their team if they gain a significant gold advantage.

• Physical Damage

  4/6

• Magical Damage

  2/6

• Overall damage

  4/5

• Mobility

  3/5

• Durability

  3/5

• Initiation

  3/5

  The higher this is, the better they are at starting teamfights and getting away with it - ending the teamfight in their team's favor.

ROLE VIABILITY

• Support0/5
• Jungler3/5
• Mid Lane5/5
• Top Lane4/5
• Bottom Lane2/5

Every time Irelia hits an enemy with any of her abilities, she gains a stack in Ionian Fervor. For every stack, her attack speed will increase by 8% (Levels 1 - 6)/10% (Levels 7 - 12)/12% (Levels 13+) up to 40%/50%/60% . When Irelia gains 5 stacks of Ionian Fervor, her basic attacks will also deal 15 (+3 per level) (+25% of AD from Irelia's items) bonus magic damage.

• Basic attacks against enemy heroes, jungle creeps, Baron Nashor, and dragons refresh the duration of Ionian Fervor.
• Hitting multiple non-heroic enemies with Irelia's abilities only give Irelia 1 stack of Ionian Fervor.
• Hitting multiple enemy heroes with Irelia's abilities gives her a stack of Ionian Fervor for each enemy hero hit.

Bladesurge is a point-and-click ability. When used, Irelia dashes towards the target, dealing 5/25/45/65/85 (+60% of Irelia's AD) Physical damage. This ability also restores Irelia's HP equal to 12%/14%/16%/18%/20% of her Attack Damage (AD).

• This ability does 55/75/95/115/135 more Physical damage to lane minions.
• If the target dies to Bladesurge (or dies within 0.5 seconds after being hit by Bladesurge), its cooldown is refreshed.
• If the target was hit by Flawless Duet or Vanguard's Edge within 5 seconds, Bladesurge's cooldown is refreshed.
• Bladesurge applies on-hit effects - like the Titanic Hydra, Trinity Force, and Blade of the Ruined King.

Defiant Dance is a 1.5 second-long channeled ability. While Irelia is channeling Defiant Dance, she stands still. While Defiant Dance is channeling, Irelia takes 50% (+7% per 100 AP) less Physical Damage. At the end the channel, Irelia lashes out, dealing 10/25/40/55/70 Physical damage at least, 20/50/80/110/140 Physical Damage at most. (+100% of Irelia's AD and +80% of Irelia's AP)

• Defiant Dance cannot be interrupted by any form of Crowd Control.
• Defiant Dance DOES NOT mitigate Magical Damage.
• Defiant Dance's damage goes in a short, straight line towards your cursor.
• Defiant Dance will always channel for at least 0.7 seconds before it can be ended early.

Flawless Duet is a two-part ability. When used the first time, it places one of Irelia's blades where you had your cursor. When used the second time, it places another blade. Once both blades are placed, the blades dash towards each other instantly - stunning every enemy caught in between them and dealing 70/110/150/190/230 (+80% of Irelia's AP)

• If Flawless Duet is not used a second time while one of Irelia's blades is planted within 3.5 seconds, the blade will go straight towards Irelia's current position - still dealing damage and stunning everyone hit by the blade on the way back.
• Irelia's blade may not return to Irelia while she's Silenced, Knocked up, Asleep, Taunted, Charmed, Terrified, Stunned, etc.

Vanguard's Edge has Irelia throw her blades in a straight line. If they hit an enemy hero, they disperse, deal 125/225/325 (+70% of Irelia's AP) Magical Damage and form a cage around the foe. If any enemies walks through the cage, they take 125/200/275 (+70% of Irelia's AP) Magical Damage and lose 90% of their movement speed for 1.5 seconds.

• All enemies around the enemy hero that got hit by Vanguard's Edge are knocked away from the target.
• Using Bladesurge on an enemy who got hit by Vanguard's Edge will reset its cooldown, but not if used on an enemy who only walked through the cage of blades created by Vanguard's Edge.

STARTING ITEMS

• Corrupting Potion - I can't think of a reason why not to buy this for Irelia at the start of the game. It gives her sustenance during the early game and gives her a cool buff. Don't try to put yourself in situations where you'll have to chug down the whole thing, though.

CORE ITEMS

• The Trinity Force - It doesn't matter what you're building or what your playstyle is, Tri-Force is a must-have for Irelia. You should build this item right away once you finish your Early Game Core. It's stats are amazing and its abilities work wonders in Irelia's hands. Once you get Tri-Force, it practically pays for itself.
• Mercury's Treads - Mercury's Treads is typically your go-to choice for boots as Irelia. It's not the Magic Resistance that helps her - it's the Tenacity. Tenacity reduces the effectiveness of enemy crowd control (stuns, sleep, roots, etc.).
• Ninja Tabi - The Ninja Tabi offers some armor and blocks damage from enemy auto attacks, but I only recommend you buy these boots if the enemy team's composed mostly of heroes that focus on physical damage (i.e Jhin mid, Caitlyn bot, Riven top, Thresh support, Xin Zhao jungle). In most games, you're going to want Mercury's Treads.
• Tiamat - Tiamat is an essential part of your early game core. It allows Bladesurge to deal damage to multiple enemies at once, allowing you to clear waves with ease and allowing you to deal huge amounts of damage in teamfights. Tiamat can be upgraded into two different items depending on your desired item build.
• The Titanic Hydra - The Titanic Hydra is the popular choice for upgrading Tiamat. It can be activated to have your next auto attack deal a significant amount of damage. Both this and its passive cleavage scale with your health pool. It's a great choice for tankier builds.
• The Ravenous Hydra - The Ravenous Hydra is an upgrade for Tiamat that is great for more aggressive players (like me). It upgrades Tiamat's cleavage to also benefit from all sources of lifesteal, allowing you to basically outsustain your enemies by spamming Bladesurge in teamfights (just don't forget to use Flawless Duet and Vanguard's Edge to reset Bladesurge's cooldown!).
• Sterak's Gage - Sterak's Gage is a popular item to go alongside the Titanic Hydra. Not only does it give you more HP (increasing the damage the Titanic Hydra's cleavage does), it also takes 50% of your base AD and adds that to your AD as Bonus AD. It also will give you a stat boost (including extra tenacity) if you lose a significant amount of your HP in combat - making it great for teamfights.

OFFENSIVE ITEMS

• The Blade of the Ruined King - The Blade of the Ruined King gives you a significant amount of lifesteal and can be used to steal a target's movement speed if needed. It also deals 8% of your target's current HP as bonus damage, making it great against tankier enemies like Cho'Gath or Braum.
• The Bloodthirster - The Bloodthirster is best built alongside the Ravenous Hydra. It allows lifesteal from your auto attacks to overheal you - granting a shield that rapidly decays outside of combat. It's a bit overkill, but it's still a very powerful item regardless.
• The Dead Man's Plate - This is a good aggressive item for tankier builds. It charges up by moving around the map, making you faster. At maximum charge, your next basic attack will deal extra damage and will stun your target.
• Death's Dance - An all-around great late game item for Irelia. It allows most of her abilities to benefit from lifesteal, gives her CDR, and allows her to mitigate damage in combat by converting it into damage over time (which is great alongside Defiant Dance).
• Guinsoo's Rageblade - Although Guinsoo's Rageblade is arguably not the best item for Irelia, there's little denial about its overall power. In Irelia's hands, Guinsoo's Rageblade synergizes with Ionian Fervor - allowing her to attack very quickly, mirroring the techniques of an ADC.
• The Mercurial Scimitar - A great item to have against an enemy team with heavy crowd control. It gives you lifesteal, attack speed, and can be activated to purge most forms of crowd control and give you a speed boost. Don't let this be an excuse to not invest in items that improve your tenacity, though!
• Warmog's Armor - Warmog's Armor is to League of Legends what the Heart of Tarrasque is to Dota 2 - a big heap of HP that rapidly restores your HP outside of combat. It goes great with the Titanic Hydra due to it's massive HP bonus alone - and it isn't the most expensive item to buy either.

DEFENSIVE ITEMS

• The Adaptive Helm - The Adaptive Helm is a great item against heroes like Karthus and Ahri - who use the same spell over and over to deal damage. It's rather situational, though.
• The Banshee's Veil - The Banshee's Veil comes second to none in protection against magic. Buying this while you're at a gold advantage against an enemy team with lots of magic damage will make you a seriously deadly threat to them.
• The Frozen Heart - The Frozen Heart greatly reduces the attack speed of nearby enemies - making it great against all enemies who deal large amounts of damage with their auto attacks - like their ADC, another Irelia, Darius, etc.
• The Maw of Malmortius - A good balance between offense and defense, the Maw of Malmortius will give you extra AD and lifesteal (for both your auto-attacks and your spells) in combat if you take heavy damage from enemy magic.
• Randuin's Omen - Randuin's Omen is the best item to build against enemies that are investing in items that improve their Critical Hit ratio (basically, every ADC ever :P). Anyone that attacks you with their auto-attacks has their attack speed lowered significantly, and it can also be activated to slow down nearby enemies. It's the perfect item to nail the enemy team's ADC to the wall.
• Spirit Visage - Spirit Visage increases the healing you receive from all sources - including lifesteal, healing from allied heroes (like Soraka ;)), and Bladesurge. It also gives you some extra Magic Resistance, doubles your base HP regen, and gives you some CDR.
• Thornmail - For those days when you want the enemy ADC to just **** off. :P
  All jokes aside, it's also great against enemies that invest into items that improve their healing in some way (especially lifesteal) - as it inflicts Grievous Wounds to all enemies who auto-attack you. Grievous Wounds reduces the effectiveness of all means of healing by a significant amount. Thornmail will also deal damage to enemies who auto-attack you, with that damage scaling with your armor.

JUNGLE HEROES

• Kai'Sa
• Kindred

SUPPORT HEROES

• Soraka

• Ahri

BOTTOM LANE HEROES

• Ashe
• Caitlyn
• Jinx
• Kai'Sa
• Kindred
• Tristana

TOP LANE HEROES

• Kai'Sa

• Uploaded this guide to the public! I hope you guys like it! :D

This guide has been long due for an update.

• Removed the popular item build and popular rune build.
• Re-organized my item builds and rune builds for specific roles (Top, Mid, and Jungle).

Glad to see you guys voting. It helps let me know if I'm doing something right. :)

• Added a chapter that details Irelia's abilities.
• By tomorrow, the list of Irelia's items should be up to par with my newer guides in terms of format and organization.
• Linked some of my other guides to boost traffic.