Annie

AoE Stun. Tibbers can be used to block (E) Bola Strike. When u jump on Annie with passive, be sure that she will stun you.

Alistar

He don't deal damage. He absorbs damage.
Never try to focus him. NEVER JUMP ON HIM. Knockup + Knockback. Your position will change quickly, i bet that he will aim for enemy team :)

Blitzcrank

Well. Scenario is simple: Your Jump, Root. Death. You will CC Blitz, but if he have R, u will do nothin. (Very Low CD)
Silence + Knockup + Flash, then Grab. Say hello to his teammates.

Amumu

If have R, suicide. In other cases? Just too tanky to get down quickly. Also % DMG is not cool, since u are Assassin, your HP will get down quickly.

Ahri

Charm, Dash, True DMG. Wooah. Even if u jump, there is a little chance, that clever Ahri just Flash, pop out the Charm, Dash away from u and deal tons of Damage. So do not let this to happen.

Gangplank

Fruits. Your biggest enemy. Root? What Root? Also Crits, (if still alive) and AoE slow. Woaah.

Cassiopeia

Never jump on Fed Cassio. Her Ultimate can turn you into a stone, and then u will die quickly. Carefull with the Snakes.

Darius

Darius is Darius. Propably he will build Armor & HP. And some AD. Remember, with his passive (Honed Blade, Apprehend) even without tons of AD, will shred you quickly. Wait! He have 100 HP! And i have 500 HP! Hooray! And then u get rekt by his Axe. (R)

Rammus

Remember, flat AD never wins VS Armor.
With Armor Penetration? Yeah, sure.
What about 300-500 ARMOR? + Damage Reflection... Oh, i forget about that. His core item is Thornmail. Wait! It's not over! Taunt :) And Ultimate. Oh, and he can chase you down with Q. (Or when you gonna jump he will use Q and u will get stunned. Watch out for this OP Turtle!

Cho'Gath

Silence, Knockup, Massive True Damage. Natural tank. (Feast). Very dangerous. Even Alone.

Fiddlesticks

If you get Fear on your Face, u are dead. Also his Core item is Zhonya. Goodluck!
It's not over! Heal Drain, Silence... Love it! Oh, when he engage first on you with his Ultimate... Words cannot describe how i feel sad for you... QQ

Fizz

Because of Trickster. (Can do nothing) And % Dmg. And AoE R that sticks on you. Nice.

Galio

Because of AoE Taunt. And who focus the tank? Lel.

Heimerdinger

If he have turrets nearby, be sure that even if u kill him, you will be dead too.
Zhonya, anyone?

Jax

Your primary damaging skill is based on melee hit. U will miss, then he stuns you, and your Savagery is gone... Very tanky. Let him use E, then jump. Or... he just gonna use E when u will be mid-air. :)

Kayle

Just because of Ultimate.

Kennen

Ultimate + Zhonya.

Lissandra

Ultimate, (Zhonya? Anyone?), Snare... Escape mechanism. Yeah, try it.

Nasus

Very hard to take down. Slow, Siphon, R that gives Health boost... Good Nasus builds a lot of armor. And that's enough.

Morgana

Because of Black Shield, and R + Zhonya. Oh, and Snare for eternity.

Sejuani

Suicide.

Teemo

Blind counters your primary DMG skill.
Also when you gonna decide to chase down this little hamster, you propably will step on Mushrooms. (Nice Trip BTW.)

Nunu & Willump

U don't have any stuns. How do you gonna prevent him from casting his Ultimate? Armor + AP is strong with this one.

Tryndamere

Look! He have 1hp! Wait... What the hell is going on? Oh, Immune. Then you get smashed in face with tons of Crits. + Debuff that lowers damage.

Vladimir

You need Ignite. And to be smart. You jump, he's gonna use Sanguine Pool. Untargetable. Woah. Natural Offtank. Watch out there!

Volibear

Do not hug him.

Vayne

This is the ADC, that can f*** u up. If u fail your Root, be sure about it. True DMG, Stealth, Stun. (OMG) Many of greedy players died because of her. So be carefull.

Warwick

Yeah, well. Warwick is top 10 1vs1 fighters. Also Bola will not help you anyway. Suppress. You have low HP? Goodluck. He will chase u down even to Nexus!

Aatrox

Passive? Heh. (Situational) If his Passive is down, you can jump.

Anivia

This is the list of the champions that u can kill instantly. Of course if u gonna do everything properly. R + Youmuu's + E + W + Q + Hydra + Smite. Remember, these champions are nothing, when engaged alone. When ADC is taking Red... Surprise! (Remember, it's situational LIST! Good ADC always stick with team, or support, when Rengo is missing. So be carefull, because sometimes someone is baiting you :)

Ashe

Caitlyn

Draven

Graves

Miss Fortune

Nami

Lux

Karthus

Janna

Jinx

Kalista

Lucian

Quinn

Sona

Soraka

Twitch

Rengar

Meow.