This is my first guide after playing the game for a while so it will be very short and to the point until i get time to go into detail. Lee Sin is insane at one on one combat and probably one of the best damaging champs in the game that can also save your teammates like a pro with his W skill and his Ulti. This build maximizes his damage output through strait damage as i have seen that attack speed isent nearly as effective for him.

Runes are simple choice in my opinion

Armor Penetration Marks : Armor penetration has been one of the strongest marks ive ever used in my opinion the only other thought i could have would be attack speed marks.

Attack Speed Seals : Lee Sin LOVES extra attack speed so any other seal in this spot would be silly because the only other seal i could imagine using would be attack damage seals but he just doesn't benefit as much in my opinion. If you need more damage get it from items in a match.

Cooldown Reduction Glyphs : This is pretty strait forward because lee sin is only restricted by his cooldowns because his energy regen shouldn't be a issue if you utilize his passive right.

Strait offensive tree masteries and i didn't care for the other talents so i got some survivability for the early game still not sure if this is the best but i will test it more. only other talent id consider is offensive mastery but i think the survivability is a better choice.

alright SHEEN is simply amazing for lee sin. Similar to how it is devastating for Ezreal's Q shot it is also amazing for Lee sins Q shot AND his Q kick if u wait 2 sec in between u can land a ridiculous amount of damage making the useless mana and AP it gives you worth it.

I personally love mobility boots just because i hate not being able to dodge an enemy gank and these usually get me away safely.

sine you already have sheen begin to built the rest of your T Force because the attack speed addition and damage + slow will help ALOT in the end

However use your judgment, if you are destroying your lane left and right pick up sword of the occult after your sheen and stack it up because it is AMAZING.

lastly most games should be nearing their end when u get your bloodthirster but if it keeps going get yourself a infinity blade and warmogs armor and that should seal the deal. I still have to do more play testing but so far this is proving to be a very good build.

Your Q is your main source of damage get it to LVL 5 ASAP as well as your E however if your feeling squishy pick up your w early to escape near death situations but only level it once! save lvling it for last! the life steal part of your W is really only noticeable at the end and it will help ALOT.

Now lee sin has many unique tactical abilities! first of all your Q. ABUSE YOUR Q it not only is a skill shot but you can hit invisible players with it and reveal them! this is AMAZING fighting akali in her smokebomb shaco when he runs away and twitch and evelyen. Secondly, your E can be used for the same thing however it is espessialy useful against akali in her smoke bomb, simply walk into the circle and use E and destroy her! third thing is your E can be used as a MINESWEEPER AGAINST MUSHROOMS!. This is absurdly usefull if u think theres a shroom nearby smash E and punch the shroom. Keep an eye on Teemo and take out each one. Lastly Lee Sins ULTIMATE ULTI. This combo does a absurd amount of damage but it looks INSANELY cool haha. Find the enemy hit them with your Q at close range then pop ur ulti to send them flying then quickly follow up with your Q again and do a flying kick into them as they go flying back and you should usually kill whoever you did this too.

I go with Exhaust and Flash because exhaust helps me when i have to beat that Yi or temmo in the face when they have a nearly 2 AS and flash will just save you from dying many times because you are quite squishy till end game.

Thats about it! Lee Sin is ALOT! of fun and is quite powerful if you play him right. Ill be updating this when i have more time but this is the general idea. Happy round house kicking!