Playing with LeBlanc the way I do it, I get 34 AP (not counting the magic pene). This gives you 138 DMG from Q (Detonated) and 105 DMG from W, so after good lvl 2 combo (Q+W) you will hit the enemy for (approximately) 180-220 DMG more or less. Considering that the champions on lvl 2 have around 600 HP this is HUGE amount of Health "Disappearing".

When you hit lvl 6 examine your enemy. Look how much HP he has left (if its below 50% do Q+R+W and see what happens, use ignite if you want to be sure). If your enemy has more than 50% hp try to use Q+W and then Q+R+E or wait for the cooldown to execute your Q+R+W and get that 300 gold!

OK, so you just spawned. Grab the pots and Ruby Crystal, and head on Red or Blue to help your jungler. TRY NOT TO USE W - it deals huge damage and can help you to harass the enemy on your lane. Just autoattack. Go on the lane and try to lasthit, and hit your enemy with W. At lvl 2 try to go Q+W, and possibly kill him. At lvl 3 you have no option but to kill him if he gets close and you have all of your spells, and ignite. Try using Q+W+E+Q (if you do it fast, the cooldown of Q will erase and you will be able to deal 479 dmg (without magic resist) but considering you don't fight vs 100% HP opponent this is fairly enough. Repeat this until lvl 6.

Here starts the fun. I can't predict the amount of dmg you will deal but I know that your combo at BASIC (34 AP) stats does 771 dmg adding the lvl 6 ignite. its only on 34 AP! Repeat the Q+W combo and finish off with the Q+R+W+E+ Ignite (REMEMBER: YOUR ULTI COSTS NOTHING!!)

Your main goal is to annihilate ADC's or APC's. How to do it?
- Try focusing them with combo in teamfights.
- Be sneaky: Go into the bushes near your enemy team blue/red and look for an roaming ADC/APC (30% chance but i did it and it works) - when you see them coming at you just let them come as close as you can (you will need this to prevent flashing out (it is possible) or you can see if the ADC doesn't have tank or full team behind him) if you do it right and have good items after one second of smashing buttons you can expect "omg" coming out of dead enemy ADC.

Difficulty: Easy-Medium
What to do: Try to evade her Orb of Deception, if you get hit by Charm try to spam move command in other direction, it can work and you wont be coming towards her (you will still be dazed though). Pre-6 she's easy to kill with Q+W+E when you evade AT LEAST her Charm. You will get some dmg from her , but you should be able to kill her afterwards.
After lvl 6 she has the option to run you down or to escape. That's why you have the option to go Q+W+E+R if needed. Just take the Fox on a leash.

Difficulty: Medium-Hard
What to do: Try to fight back but don't let her Detonate the Mark of the Assassin as it deals massive dmg early. Pre-6 you can deal much more dmg then her but be aware of her ultimate - most likely she won't fight just after getting her Shadow Dance, but when she has at least 2 stacks to deal even more dmg or to jump out if it get's too heavy. You need to kill her as many times as you can before she gets lvl 6 and if she sttacks you and it goes bad just use Distortion to get away.

Difficulty: Easy
What to do: Whether or not she has stun you can hurt her BADLY - she has huge attack range, but her Con is very low health. Feast on her but be aware of her stun and jungler. If you screw up you can feed her and let her get tanky with Rod of Ages which will make your work harder.

Difficulty: Easy-Medium
Brand can be medium matchup because of his damage on Pillar of Flame+ Sear combo which can be a problem to you. If you manage to evade one of these skills you are free to make the fire elemental taste his own medicine and give him hell.

Difficulty: Hard
She can be hard with her , and and . After spamming these she can just use Petrifying Gaze on you and finish you off. If you manage to evade the skills (they are smartcasts and not everyone aims them good) and ask for help you should be okay.

Medium-Hard
What to do: His Troll pole can be annoying but his cooldown is high. Use to force him to use his Troll pole, wait 3 seconds and wipe him out. If he tries to engage try to Q+W him and he should use the pole to escape with his tail between his legs. Avoid the fish at all costs and you should be fine.

Difficulty: Medium-Hard
What to do: Firstly, try not to get poked with her Bouncing Blades. Stay near minions, but if you see that she uses her Q move away, and the blade should do you no harm. Be aware of her Shunpo and that she can TP to her minions, wards, you, your minions, YOUR fresh wards (visible for her), also, that gives her 15% ALL damage reduction for 1.5 second. When she jumps on you with Death Lotus best option is to use Distortion and wait for the cooldown to reset.

Difficulty: Easy-Medium
As in Annie's case, this lady has enormous range, but its not on her autoattack, but on her skills. Her Lucent Singularity can be a pain, but if you get some magic resistance you can nullify most of the damage, and kill her because just like Annie, her HP is relatively low for your skills.

Difficulty: Easy-Medium
What to do: When you are shielded by your little companions she cant get you with her Javelin Toss, but be aware that she can place Bushwhack in minions to give her the stack of Prowl and in consequence jump on you.

Difficulty: Hard
What to do: Try avoiding her ball and ask for help. You don't want to risk jumping on her, getting the ball hit you when she shields herself, and getting combo in the face.

Difficulty: IMPOSSIBLE
If you see guys picking Sion vs you, you should know that you are in for a wild ride. He will just shield himself and stun you, detonate the shield and repeat this until you die or give up. Believe me, you won't be able to live long laning with him, he's my counterpick if enemy takes LeBlanc for me.

Difficulty: Medium
Swain is a champion rarely picked, nonetheless he CAN be annoying. If you manage to avoid his Nevermove jump on him even if he uses his Decrepify or Torment. Don't let him get fed and get his Rod of Ages, and his Ravenous Flock will be less thread than usual.

Difficulty: Medium-Hard
Her balls can be annoying, but if you manage to dodge her spells, and don't let her hurt you and kill down with Unleashed Power you should be able to win the lane.

Difficulty: Easy
His Wild Cards have smallest hitbox in the game, being easy to dodge. If you are fast enough he wont be able to Pick A Card before you combo him and he will die looking at Ace's :P

Difficulty: Depends on the game. From Trivial to Very Hard
Playing vs this little Yordle can be tricky - you cant evade his Baleful Strike and if you dash through his Event Horizon you will be stunned anyway. His Primordial Burst scales with YOURS AP so this is a double edged sword - the stronger you are, the stronger he hits you. You can dodge his ultimate with Zhonya's Hourglass to surprise him.

Difficulty: Medium
What to do: Playing vs him depends on your skill. You need to predict his usage of skills and respond to them. Don't get all of his skills head on and try to repay him sometimes. At lvl 6 watch out for his ultimate it has insanely long duration.