Akali is an assassin champion. She is very interesting to play because you can trow an mark in your enemy and after dash in this and inflige more damage with your auto attack.

http://leagueoflegends.wikia.com/wiki/Akali

Akali's first two attacks are empowered. The first strike heals her, and the second strike deals bonus magic damage. Twin Disciplines will recharge itself automatically a short while after being used.

Cost: 60 Energy
Range: 600

Akali spins her kama at a target enemy to deal Magic Damage and mark the target for 6 seconds. Akali's melee attacks against a marked target will trigger and consume the mark to cause additional damage and restore Energy.

Akali throws her kama at a target enemy to deal 35/55/75/95/115 (+40% Ability Power) magic damage and mark the target for 6 seconds.Akali's melee attacks against a marked target will consume the mark to deal 45/70/95/120/145 (+50% Ability Power) magic damage and restore 40 energy.

Cost: 60/55/50/45/40 Energy
Range: 270

Akali teleports to a nearby location, leaving a cover of smoke at her previous location. While inside the shroud, Akali becomes Invisible and gains Movement Speed. Attacking or using abilities will briefly reveal her. Enemies inside the smoke have their Movement Speed reduced.

Akali teleports to a nearby location, leaving a cover of smoke at her previous location that lasts for 8 seconds and slows enemies within its area by 14/18/22/26/30%.While inside the shroud Akali gains Invisibility and 20/40/60/80/100% movement speed. Attacking or using abilities briefly removes Invisibility.
Stealth - Invisible: Akali can only be revealed by nearby enemy Turrets or True Sight.

Cost: 60/55/50/45/40 Energy
Range: 300

Akali flourishes her kamas, dealing damage based on her bonus Attack Damage and Ability Power. When Crescent Slash kills a unit, it has a shorter cooldown.

Akali flourishes her kamas, slicing enemies for 70/100/130/160/190 (+80% bonus Attack Damage) (+60% Ability Power) physical damage.If Crescent Slash kills an enemy, its cooldown is refunded by 60%.

Cost: 1 Essence of Shadow
Range: 700

Akali moves through shadows to quickly strike through her target, dealing damage and consuming an Essence of Shadow charge. Akali recharges Essence of Shadow charges periodically, max 3 stacks.

Akali quickly strikes through her target, dealing 50/100/150 (+35% Ability Power) magic damage.Akali stores an Essence of Shadow on kills and assists as well as every NaN seconds up to 3 total.

One Shot Combo : (if you are in 1vs1 for faster kill)

Q -> R -> AUTO ATTACK -> E -> AUTO ATTACK
OR
W -> Q -> R -> AUTO ATTACK -> E -> IGNITE -> AUTO ATTACK

Speed Damage : (if you are in fight with 3 or more ennemies)

W -> Q -> R -> AUTO ATTACK -> E -> R (on creep for escape)
OR
W -> Q -> R -> AUTO ATTACK -> E -> IGNITE -> AUTO ATTACK -> R (on creep for escape)

ESCAPE COMBO : (if you need escape a fight)

W (backside a wall)
OR
W (backside a wall) -> FLASH
OR
R (on creep for escape)