Because you came for a quick read while the screen is loading here's the TL;DR version of what's bellow...

Smart Cast on Q and R
Summoners spells are HEAL and FLASH!
You go mid!
You gank when you have boots
Your killing combo of death is Q - R - W - W/E
If you're sure you're gonna hit R - Q - W - W/E
When you can't get close: W - Q - R - W

04/05/2011
Someone explained to me that expanded mind doesn't work how I was convinced it does, so I updated the masteries to reflect that

03/05/2011

Changed a comment that was wrong about magic pen, noone noticed though
Had, by mistake, posted flat mana seals, it's regen seals you should use, fixed
Added Change log
Added FAQ
Changed latest games screenshot
Added Surviving Section
Added Pantheon on 1v1 tips
Added Master Yi
Added Tryndamere
Added "What this guide is NOT" section

How do you farm with Leblanc?
You gank; Early on you can't kill creeps fast enough with any spell and you need the CD of W to kill enemies or get way. Later on you kill stacked minions waves really fast with W - R;

Why not smartcast on W and E, and how does smartcast help you?
Because W is an AOE and it helps (at least for me ) to see who I'm hitting and where I'm landing and E because it's a skill shot (and personaly I find hard to use them without the pointing arrow :\ ).
Smartcast on Q and R helps you make the Q - R part of the standard combo REALLY fast.

What happens if you can't keep up stacks?
Trade it for something that will help you against what's killing you... more on that later I guess.

Omg! Hunting Guise instead of Void Staff???

Later on if you have extra gold and the other team is stacking MR like a boss you should trade it for Voidstaff, you shouldn't follow any build to the letter, adapt to the situation people... Personally I've only did this once, with haunting guise tanks with MR also drop...


Heal, really? Why not ignite
If have Ignite I'll use about 3 times early on to get a kill faster...
If I have Heal I'll use it through the entire game...
That make it much, much, more useful.
(3 kills vs several times heals saves me or teammates)

Ok, I've been playing this build for a LONG time, almost since Leblanc came out, but I have't made a guide out of it yet because I wanted to keep it all for myself... However a few good guides sprung since then, more people have been playing leblanc, but I haven't seen this exact build around.

The purpose of this guide is to build the most damage output possible Leblanc, you survive by killing the other guy first..

Also this is my very first guide, I'll make corrections to mistakes I'll probably make ahead... Also I don't know how to make items/skills/spells/wtv appear here with an icon like most guides have :(

Very important: Make sure you have Q and R on Smart cast!

I've spelled out the order I buy the items - including the recipe ingredients, however, you SHOULD buy health potions with left over gold after each item or base visit so you can maximize your lane/team-fight time.
If the game isn't going well, you can skip the soulstealer, but you should be raking stacks even if your team is loosing...
here's a proof of concept:

If you manage to get 20 stacks on it you'l make tanks cry and squishes will disappear in your wake.
If the game lasts long enough you replace Doran's Ring with Deathfire's Grasp.

Runes, they're straight forward, magic penetration and mana regen, if there were magic pen seals I'd get those instead though.

The masteries are pretty generic caster, you can swap around the points in utility master, blink of an eye and greed as you please.

When I first started I used Flash and Ignite... Flash is very useful, you can use it to get away and to catch those little bastards who are just out of range, ignite however loses it's usefulness, early on you get a couple kills with it against people who'd get lucky, but mid/late game you barely use it :\
After many tests the most stable combo I found is HEAL + FLASH
But heal is a noob spell you say? Kinda, but you're going mid, it will make a difference, you're made of paper, it will make a difference, you can tower dive with it, it will make a difference, you can save teammates - it will make a difference.

You go middle lane, period.

Early on you try to last hit minions... play defensive, but, every chance you get, use Q on your opponent, your purpose is you get him to about 50% by level 4/5 (if you can't make a kill before that, which is kinda hard tbh).

Try not using other spells other than Q, you might make your opponents forget you have them or think you can't use them - I've found that this will get more surprise kills early on, trust me.

Once you're level 4/5 the magic should begin, (remember you got the enemy champion at 50ish% hp?) idealy you will hit him with Q, then W right at them and finish with E, if they don't die (nor heal*) they should be very low hp, so use heal now, and wait for Q to come out of CD to finish them off. This is the standard first kill... Your experience may differ :P
(*if they do heal, you should recall W to retreat and wait for another opportunity)

Once you got your boots (about lvl 9 I believe) you can start ganking, look for lanes where your opponents are pushing and go there, pick the squishier/lower hp target and do Q - R - W ( -E if it didn't die )

You should be the pro ganker of your team, smart enemies will have picked on this, you might need to hold off melees running towards you with E and killing the on the spot later.
If you're really good, they'll start calling you hacker and cheater by now :D

Once the team fight part of the game begins, try to stay behind the tank, but not too far behind, you should kill everyone who is foolish enough to get in your range.
Don't be afraid of hitting people under the tower too, if they're not attacking you they're dead.
During this part of the game you'll be doing more:
Q - R - W - W
You'll be using recall of distortion to get away from the mess/under the tower, you won't always get a kill with it, but you'll get assists and not die, which is kinda important.

If there's time and opportunity ask teammates help on getting the blue buff (it's not like you can't do it yourself, but it costs a lot of hp and you don't have much of it).

When mid against...
Nidalee: You'll seldom get a kill, sorry, the heals are just too good >.< boring games >.<
Long range Champions (like sivir, lux...) use W to get in range of Q, it's the only time I recommend using W earlier. Also you'll get a kill from W - Q - E...
Self healing champs: you're going to have some trouble here, they can probably out heal your mana, so don't push it and have patience...
Vlad: try to hit him after each time he uses his drain...
Teemo: buy a ward at lvl 6 to neutralize his mushrooms and place right in the middle of the map.
Katarina: pay attention, try not to get hit by her bouncing knifes thinggie, be on your toes, when she does her ulti you CAN kill her before you die, requires some luck, and reflexes of steel, good Katarinas are a hard match on mid.
Anything Stealthed: BUY A GOOD DAMN WARD :|
Pantheon: If he stuns you on 1v1 you can kill him right after that and if you're fast enough you can finish him before his cone strike is over... Also, learn to time is ultimate, when you see the big red circle, move a bit away and aim E to the middle, you should make him land chained.
Master Yi: You'll see Yi's often using alpha strikes on minions and then running back (to under the tower or to teammates), so, when you see a Yi doing alpha strike and you suspect it's target at you minions, get closer to your minions (if safe) and get ready to nuke Yi as soon as he pops back. You can also do this when he alpha strikes against a teammate of yours - basically when a Yi disappears to do alpha strike he's screaming really loud "look at me I'm gonna get into your combo range!".
Tryndamere: Learn the sound of his ultimate! If he's running towards you, your combo should finish him before he has time to realize he has to use his ulti. If he charges at you using his ulti (and full hp) he's a smart player and you should dash with W and try t hold him with E to wait out his ulti. If he's using ulti on a team fight (not aiming at you) use E to hold him in place so he dies when the ulti is over.

Leblanc is one of the hardest champions to 1v1 against, however you ARE made of paper here, so should you need to run away you have several options.
You can use W to dash forward away from danger and through walls, in case they keep coming after you you can do it again with R.
Know your enemy. If you know an enemy doesn't have ranged attack, or ways to get near you enough or you know their abilities are in CD you can slow them and hold them into place with E.
If an enemy tower dives toward you, you can dash away with W and lock them under the tower.

This guide is NOT an absolute written in stone best thing ever.
The worst mistake you can do when following any guide is doing it to the letter without adapting to your situation...
Too much CC? Quicksilver Sash
Too much casters? Banshee's Veil
You're not getting targeted at all (other team is braindead) switch Will of the Ancients with Voidstaff, Archangel's or Crystal Scepter.
You don't like the masteries? Change them, any generic caster mastery works

I've heard I'm supposed to have a bunch of screenshots here to show off my awesomeness with this build... but the fact is that I just don't...

I'm currently playing lol with the sole purpose of adding screenshots here, but having a tight schesule I can't play many times a day..
here's the latest three:
(the bot game was to check the lag... the other two were surrenders...)