Irelia

Strengths

Use Bladesurge to cover great distances by targeting low life minions on your way to champion targets.
Defiant Dance is not interrupted by crowd control, try timing it for incoming disables.
Flawless Duet does not have a maximum travel distance, try using it in creative ways.

Passive · Ionian Fervor — When Irelia strikes enemies with spells she gains stacking bonus Attack Speed. At maximum stacks she also gains bonus damage on hit.
Q · Bladesurge — Irelia dashes forward to strike her target, healing herself. If the target is Marked or dies to Bladesurge, its cooldown refreshes.
W · Defiant Dance — Irelia charges a strike that deals more damage as she charges. She takes reduced physical damage during the charge.
E · Flawless Duet — Irelia sends out two blades which converge on each other. Enemies caught in between are damaged, stunned and Marked.
Ultimate · Vanguard's Edge — Irelia fires a massive number of blades that explode outward upon hitting an enemy champion. Enemies hit by the blades are damaged and Marked. Afterwards the blades form a wall that will damage and slow enemies that walk through it.

A suggested 5-lane lineup built around Irelia, based on hero partnerships and role synergy — not win rate.