Lee sin is a very mobile champion with the ability to become pealer, bruiser or assasin however if you are playing him froggen style then you are probably the assasin type mentioned, i only recommend the build above if your doing just that.

well if you are checking out this guide you are probably a froggen fan, and if you are not you should probably go watch some of his plays on youtube. Lee sin's ability to gap close harass and farm makes him able to contend with any mid and it is known that auto attackers or atack damage dealers in general tend to hit way harder early game, and lee is just that an early game powerhouse you will utilize your love of skillshots and skilled plays to make everyone jelly of your moves.

Well for starters you should not be playing him mid unless you feel confident with him overall try easier things, like jungle or top and for those of you who like to fool around try support but thats enough of that, lee allows you to roam because of his mobility and unlike most mid casters lee can easily clear our a wraith camp at mid without missing any cs and barely any health, dont worry about pushing your lane as that will happen if you are not carefull with your tempest/cripple just try to either farm wraiths or roam till the wave is pushed back, however you have a very strong zonning and/or killing potential early on, some things you can do at mid is that if you see them going in to grab for cs, just safe guard that minions and try to tempest/sonic wave them in the face and move back if they try to trade with you they will most likely lose however becarefull as this tactic could be dangerous near their towers.

Harassment combo:
Q>Q>AA>AA>E>W ( if you dont need to w away dont, but this will drain your energy pool hard so be careful, Try to fit in 1 auto attack at least otherwise the energy cost might be too much)
Your Most used damage oriented Combo:
Q>(ignite if possible>R>Q
If they are up against a wall and you can kick them without making them go over it :
Q>E>(Ignite if possible>R>Q
Escape Mechanics:
E>W>E ( Will slow them while you are headed away from them )
Q>Q>W ( If you are near any jungle camps such as wraiths)
Advanced escapes:
Ward>E>W>E ( Place your ward over a wall or as far as you can jump to it slow them then run )
Impossible Escapes:
Flash>ward>W ( Q>Q to any nerby jungle camps if possible ) Just as stated you are almost impossible to catch.

These arent all of the combo's you are capable of but be careful when trying to execute them as always map awareness is key!

Alright so here we will take about your Possible Lane match ups, things you would like to alternate with skill order or item build!

Ahri:(Difficulty) 3/10 Easy
Ahri like most mages suffers from a weak early game and high cool down on her cd's her main harassment is her Q a skill shot if you can avoid it then you are well on your way to winning the lane, you have a much higher damage output early on. Abuse that and control the lane as hard as you can, zone her as much as you can and keep her away from exp as mages scale better with levels than items.
Combo: Q>R>E>W>Q>R>R>Q>ignite>W you should really be dead if she hits you with all of that ****. dont let her.
Akali: Difficulty: 5/10 (Easy to medium)
Akali is really underplayed after all the nerf's shes received and she honestly hates lee sin along with shaco and talon, but her main harassment tool is her Q she has a really weak early game you have a really strong one the only reason that this lane could be a 5/10 is because after 6 her kill potential rises but however your's does even more as long as you dont let her free farm passively and shut her down early she cant do much.

Common Combo: Q ( Then she waits untill her Q goes of Cooldown) Then she R's you and q's you auto's then E's you, If you dont kill her by then you should be dead.

Anivia: Difficulty 2/10 (Might as well go AFK and make a sammich)

Anivia is probably the easiest champion for lee to get paired up against, slow skills hots high mana costs and a low health pool and really weak early game makes her, hate lee like no other if you lose this lane you might as well be a potato ( in which case you have a better chance of winning the lane).

Harrass Combo: Q>E
All in combo: R>Q>E>E
Just use minions to dance around her, her wall cant get in the way of your Q, rape her.

Annie: Difficulty 6/10 ( Easy to medium)
Just like most mages you can shut her down hard early just q her face and go back with your w she will try to farm with her q whenever you see she wants to do that try to safe guard the minion or kick her in the face, and hopefully she might miss out on the mana return from the Q Kill, which will make her cry. However at level 6 she can pretty much Burn down your entire health pool, annie players usualy use a Flash>R>Q>W Combo that deals tons of damage if you shut her down really hard early then your Ok but if you feel like she still has the potential to burst you down, rush hexdrinker otherwise youll be fine.

Kill combo: Flash R>Q>W>Ignite if you arent dead then she should be.

Brand: Difficulty 5/10 (Easy to medium)
This matchup is pretty much in your favor as long as you play it wise and dont give him any lead early this lane is yours the only way a brand could burst you would be if you just stood in his combo or got stunned which you shouldnt as a lee player anyway, if you feel like you ****ed up with him just rush your hexdrinker, otherwise play an in your face early game and try to be everywhere he is at midgame he will hate your guts.

All in combo: E>Q>W>R Try to to not to give him a clear shot or your ****ed.

Cassiopia: Difficulty 7/10 (Medium to hard)
Just one of those mids you dont wana play against its really skill related but if she is any good, when you get close to her she will just Q your face and E spam the hell out of you, Defenitly rush your hexdrinker and try to avoid all of her skillshots otherwise your skill order should stay the same, ask jungler for a gank or risk dieng in a 1v1 up to you.

Combo: Q>E>E>E
Kill combo>Q>W>R>E>E>E>ignite if she can. dont get caught in her ult stun and she wont do it.

Diana: Difficulty 4/10 (Really easy to medium)
Depends on player skill but you mostly got this high mana costs early on and a small health pool just q her in the face whenever you can and zone her at 6 she becomes a bit of a threat just play your cards right and combo her properly and this is as easy as cake.

Combo : Q>R>W>E>Q>R>R dont get hit by that intial Q and you got her without an ult for nearly 20 Seconds.

Elise: Difficulty 2/10 ( Might as well take a nap )
She is really underpowerd right now you might as well just afk you own her at all levels just get in her face and Q her, dont let her get free Q's on you otherwise she cant trade for **** probably the easiest lane for lee atm..

Elise dosnt have any sustain, abuse that fact Just keep Harrassing her with Safeguard and tempest. then finish her with your QRQ or Flash QRQ ignite combo..

Evelynn: Difficulty: 3/10 (Sammichs anyone?)
So evelynn is like that champion that you were built to counter in reality lee was built to counter most stealth champions, when you trade with her just make it brief Q/E her in the face and get out you dont want to eat her q's for a long time all she can do is escape you at level 6 her kill potential rises but nothing for you to be afraid of just play it smart. she can escape your Cripple but just make use of her squishiness and punt her in the face after she has used Her W

Combo: E>R>Q>Q>Q
FiddleSticks: Difficulty 5/10 (Medium)
Honestly fiddle will beat your *** from 1 to 5, you just cant trade with him with that w of his, once you hit level 6 just get in his face and QRQ him make sure he is life draining you first though, he has a small health pool try to force him to stay in lane till 6, you got this fiddle cant last hit for shift, if you feel like he is damaging you too much just push the lane and do wraiths or roam thats about it.
Combo: E>Q>W You cant avoid half his combo Just try to stay in a bit of a range far from him, becarefull when aproaching the bushes mid lane as he might jump you and rape you at 6.

Fizz: Difficulty 7/10 (Medium to hard)
Depends on the player but usualy fizz is one annoying ***********er you will have a hard time trading with him if you feel like he is going to Q you, do the same and if he does try to tempest/cripple him, if you cant just Sonic wave And safeguard to a minion as fast as possible, this is pre 6 at 6 it gets really tough his ult will hurt alot and his combo will rape you, but if you play your cards right you can kill him as well with a high damage combo (Q>IGNITE>E>R>Q) Not easy to pull off but probably your only chance to kill him
Note: Try to make him use his playfull/trickster before doing the combo.
Fizz combo: R>Q>W>E>Ignite>Q meh just try to avoid his ult otherwise bait his playful/trickster.

Galio: Difficulty 2/10
High mana costs early, was built to counter mages, you arent a mage just beat his face in with your manly fists. his w can be annoying but he cant last hit for shift push the lane whenever you want he will almost always lose CS because he is melee with barely any mobility.

Gragas: Difficulty: 5/10
Just shut him down early as he has a weak early game and he wont get in your face later on, dont and you will regret it becarefull at level 6 an all in might be ur loss if he is worth his meat. his ultimate will displace you hard and he will get to e, q you try to have him marked with Q when he does that so he dosnt get a chance to combo you..

Heimer: Difficulty: 6/10
None plays heimer mid anymore so dont worry, but honestly he is annoying you cant trade with him early game because of his turrets, just rush hex drinker and beat his *** once you hit 6 try to Flash Q > R > Q him away from his turrets. otherwise just avoid being hit with those stupidly high ranged rockets of his, he can last hit pretty well but if he misplaces turrets he will push the lane giving you free farm.

Karthus: Difficulty 3/10
Just beat his ***, he is squishy and all you need to do is move between auto atacks to avoid his Q when you are going in for a kill or trade he has no chance of winning the lane against you, unless you push in which case karthus will just sit at the tower for the next 4 waves and farm them. Dear god just dont get hit by his damn wall and if you do use your abilities to Juke his Q's or you will be eating them for free~!!

Kassadin: Difficulty 5/10
Kassadin is a counter-mage you are not a mage sure you cast spells but silence cant do shift to you, he is squishy pre 6 just beat his *** with your q's after 6 just bait his Void walk and combo him as fast as you can he be really nasty because of his roaming and slow but otherwise you got this.

Katarina: Difficulty 5/10
well you both have infinite resources and leaps its not hard for lee to win this lane but be warned a good kata will not let you zone her in which case you have to be very careful on how you treat her at 6 because if you are low health you wont have enough time to Kick her out of her ultimate my advice is to q her and wait for her to ult and then ult her and q her again you probably wont land a killing blow unless she is stupid enough for you to be able to combo her at such low health, she will push the lane early on because of her Q, take advantage of that.

Kennen: Difficulty 5/10
Just shut him down early on when he is weak and you have nothing to worry about, even though i dont recommend trying to go in for kills as he has a good ability to stun you and then E away but do the same for him if he gets stupid and gets close to you E him and if he tries to E away cripple him he wont win early trades as long as you dont eat free shrukens, its a more skill orianted matchup but you should win, at six it gets really risky for you a good kennen can stun you around 3 times, grab mercs as soon as you can.

Leblanc: Difficulty : 3/10
Just beat her as hard as you can dont get hit by her ******* E and she will become irrelvant after a while as she cant farm and dosnt provide anything for her team, take advantige of that. if you for some reason start to lose this lane, (Jungler pressure or whatever) just push the lane and roam / or farm wraiths she cant farm as well as you and she cant push for shift.

Lux: Difficulty: (?)
This is a completely a skill orianted matchup lux can be either horrible and feed you like no other or land impossible bindings and make you hate your life, she can farm and sustain and she has a shield and a snare i suggest you dont go crazy on kills or she will lazor your face back to LALA land.

Malzahar: Difficulty: 7/10
You shut him down early however at 6 you probably just wana try to push the lane and roam/farm wraiths as you will most likely not win a 1v1 thanks to his Pool E that silence and ultimate, you dont really wana play against him, infact i deem a 1v1 suicide get your jungler to help otherwise dont 1v1 him after 6! (Defenatly rush hexdrinker)

Mordekaiser: Difficulty 6/10
You will only win untill he gets his revolver at which point you just wait at the turret after he pushes the lane ( he will) and just free farm not hard, he cant turret dive you unless your low dont bother 1v1ning him you will lose (After Revolver!).

Morgana: Difficulty 5/10
Dodge bindings and farm the lane its just gona be a push fest as you wont be able to make her commit to a fight, thanks to spell sheild just stay at turret and push back the lane whenever it gets there, i dont recommend freezing it since she cant toss her W's under your turret its not a scary lane just dont get reckless and get caught at 6, unless you wana die that is.

oriana: Difficulty 4/10
Weak early game punt her as hard as you wish even at 6 she isnt that much of a threat her mana costs are crazy, low health pool as well abuse that.

Ryze: 8/10
You shut him down early until he hits 6 in which case if you try to combo him or anything he will just snare you and throw **** at you like there is no tommorow just dont try it after 6. keep farming and roaming or get a gank thats all. even though if he does waste his snare and you can flash Q>R>Q him to your side of the map give it a shot you might be able to kill him, or feed him it depends on how good he is.

Swain: 9/10
You just had to go there didnt you, swain is the most obnoxius mid to play against, a ****load of sustain a Dot and a snare everything lee hates he is ranged so you cant do much in terms of harassment Pre 6 try to harass him but dont get caught *which is going to be hard* after 6 dont even bother, call for a gank or dont even bother and then just roam or farm, but otherwise you will never win this lane especially if he rushes a ROA.

I forgot to mention this is my first guide on mobafire be nice, and leave constructive feedback! thank you for reading!
Note: Only take the hyper damage build if your snowballing like crazy and you are sure that you will continue to snowball!