So you've picked the blind monk ah ? well, let me tell you a little about Lee Sin. For one, id say he's one of the best harassers in the entire LoL Community, he can get in and out of a fight in a second no flash or ghost needed, all skill.. literally.
Lee sin is a champion that takes some practice to get used to but once you have the right build you are set this offensive tank can sure send some furious kicks to his opponents.

1. Flurry (Passive)
After Lee Sin uses an ability, his next 2 basic attacks gain 50% Attack Speed and return 15 energy each.


2. Sonic Wave/Resonating Strike (Q)

50 mana
Cooldown: 11/10/9/8/7 seconds

Sonic Wave: Lee Sin projects a discordant wave of sound to locate his enemies, dealing 50/80/110/140/170 (+80% of Bonus AD) physical damage to the first enemy it encounters. If Sonic Wave hits, Lee Sin can cast Resonating Strike for the next 3 seconds.
Resonating Strike: Lee Sin dashes to the enemy hit by Sonic Wave, dealing 50/80/110/140/170 (+80% of Bonus AD) physical damage plus 10% of their missing Health (Max: 400 damage vs. Monsters).

3. Safe Guard/Iron Will (W)

50 mana
Cooldown: 8 seconds

Safeguard: Lee Sin rushes towards a target ally, shielding them both for 40/80/120/160/200 (+80% of AP) damage over the next 5 seconds. If a shield is broken, half the energy cost is returned. After using Safeguard, Lee Sin can cast Iron Will for the next 3 seconds.
Iron Will: Lee Sin's intense training allows him to thrive in battle. For 5 seconds, Lee Sin gains 5/10/15/20/25% Lifesteal, Spell Vamp, and 5/10/15/20/25 Armor.


4. Tempest/Cripple (E)

50 mana
Cooldown: 10 seconds

Tempest: Lee Sin smashes the ground, sending out a shockwave that deals 60/95/130/165/200 (+60% of Bonus AD) magic damage and reveals enemy units hit for 4 seconds. If Tempest hits an enemy, Lee Sin can cast Cripple for the next 3 seconds.
Cripple: Lee Sin cripples nearby enemies revealed by Tempest for 4 seconds, reducing their Movement and Attack Speed by 30.0/37.5/45.0/52.5/60.0%. Movement and Attack Speed recover gradually over the duration.

5. Dragon's Rage (R)

No cost
Cooldown: 90/75/60 seconds
Lee Sin performs a powerful roundhouse kick launching his target back, dealing 200/400/600 (+150% of Bonus AD) physical damage to the target and any enemies they collide with. Enemies the target collides with are knocked into the air for a short duration.


1. Flurry: Flurry is a tricky one because after Lee Sin uses an ability, his next 2 basic attacks within 3 seconds gain 50% attack speed and return 15 energy each strike.

Note: with Flurry be sure to stretch out your abilities to get the maximum potentialFlurry will give you.



2. Sonic Wave/Resonating Strike: Lee's get in move also real damage ability and his harass ability, his Q is a skill that once it hits an opponent or neutral monster, Lee Sin will fly through the air delivering a devastating kick to whoever you hit with Sonic Wave first.

Note: Use this move whenever it is off cooldown, you dont have to use both the skills just the first one to harass, once you have Safe Guard/Iron Will Use Sonic Wave/Resonating Strike To get in, and Safe Guard/Iron Will to get out.

3. Safe Guard/Iron Will: This is your get out move, Also your shield , this skill is pretty straight forward, activate for your passive to kick in, or to use when you want to get out of a In/Out harass.
Also this ability is good to shield allies and yourself from some on coming damage.

4. Tempest/Cripple this is your skill you use when you first get off that Sonic Wave'Resonating Strike as soo as your in that fight and your passive has passed, use Tempest wait till passive is gone again then press E again to Use Cripple always use your passive to its potential to have the max damage out put as fast as you can.

5. Dragon's Rage Just a complete pain in the *** if you hit it right, what i like to do is flash or Safe Guard/Iron Will ( if there is a minion or champion in front of the opponent) and just Dragon's Rage his *** back into the entire team for an awesome gank that is almost always going to work if pulled of right.

As you can see, this build has its pricey items.. who am i kidding there all nice priced items, so be sure you farm as fast as you can to get some leverage on your opponents.

TIP: 1. good way of farming early is to gank mid obviously, just early on head to mid, hid in the bush and just try to get the kill with mids help.

Flash + Exhaust

Alternative

Flash + Ignite

these 2 are summoner skills no matter witch one you decide to use is just MONEY, and FAST.
these 2 spells will let you kill your enemies as fast and easy as it could ever be. so enjoy.