This guide will be for Jax. First off, this guide was discovered by a player in high elo that I am sure a few people have seen, but the name hasn't come to me. Though, I noticed a guide of the build hasn't been put up, so I'll do my best to intimidate it.
Now, getting to know Jax.
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Jax Abilities, Skill Order, and a Tip for Maxium Damage Output!http://img824.imageshack.us/img824/6756/jaxabilities.png
For his skills...
R>Q>W>E
As such, from level 1 | 2 | 3...
Q | W | Q | E | Q | R | Q | Q | W | W | R | W | W | E | E | R | E | E |
To start fights, you should always use his Q to close the range and for some extra damage. If you have a Sheen, using your jump will activate it midair, and then use it upon the hit.
Follow this up, even midair, with your W for the full damage burst of Sheen Double Damage, Q Damage, W added damage, and your auto attack all in one swing.
At level two, with no sheen, you'll hit for about 350 damage on average.
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Runes, Masteries, and Example!http://img220.imageshack.us/img220/3775/jaxmasteriesandrunes.png
For this, you will want...
3x Flat Damage Quints
9x Flat Damage Seals
9x Flat Damage Marks
9x Flat Magic Resist Glyphs
The reason for this is for Jax's strong early game farm, champion domination, and health benefit from his passive.
Most champions start with about 70 attack damage and around 600 health at level 1, so needless to say Jax will have the 1v1 advantage over them.
For the Masteries, you want 100% assurance of your abilities (Given Damage, Given Ability Power, Given Armor Penetration) versus chance (Critical Strike Damage, Increased Critical Strike). What this means is that you know your damage is standard and heavy versus hoping for those crits to be your damage output. With this masteries listing, you get the most for your damage output and you benefit from armor, magic resist, and gain dodge/speed when you dodge. If you choose not to use Ignite and Exhaust like I do, then those may be switched out.
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Summoner AbilitiesFor Jax, there are a few simple abilities that are very useful to him and I suggest no others.
Flash Ignite
Flash Exhaust
Exhaust Ignite
Ghost Ignite
Ghost Exhaust
Those are the only combinations period, being that you have either Ignite or Exhaust on him at all times, and then choose either...
*Flash
*Ghost
*Ignite/Exhaust
I do not recommend anything else, as I think Teleport, Ghost/Flash combo, Cleanse, or any others would be wasted.
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Items1) Buy Dorans Blade.
2) 350 Boots + 2-3 Potions.
3) Upgrade Boots to Ninja Tabi's -> 2 Movement speed and Dodge.
4) Go into the Rageblade, buying the Pickaxe first.
5a) If you need bursty damage, go Sheen into Triforce.
5b) If you need overall damage output, go Pickaxe into Gunblade.
6) Get the other item from 5A or 5B.
7) Get B.F. sword into Bloodthirster.
8) Situational : Typically some sort of Magic Resist item or Defensive item.
In the end, your build should be something like...
Boots | Triforce | Gunblade | Bloodthirster | Rageblade | xxxxxx
You can switch out Rageblade for a Phantom Dancer in the end if you like, as this will help you get close to your attack speed cap immediately instead of building stacks with Rageblade, as well as move you faster. Sell off the Dorans blade when you need space, but don't sell it off before the Sheen in triforce.
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Finishing TouchesIn the end, Jax is a very heavy damage dealing melee attacker. He can be a great fight starter with his Q into W combo, only to AoE stun everyone around him if he dodges. With all of this damage, you will have about 3,000 health in the end with VERY high life steal, attack speed, spell steal, and a item Use-On-Effect as well, very useful to slow enemies or deal a extra 300 damage flat that is needed.
For full effect of damage, try to get the Ten stacks on your R along with making the Third Attack ready to strike (For extra magic damage) and have a sheen, then open with a W, Q combo (Using W to simply get it ready for when you hit, as well as procing your sheen), Landing on them for a good chunk of damage, and finish them off with a Ignite/Exhaust or both along with any stuns you can do and a Gunblade use.
In Short... W+Q onto them, R and then E whenever you can with Exhaust/Ignite/Gunblade used too.
As such a heavy attacker, your job will be to squish the squishies and to aoe stun as much as possible!
Good luck, and enjoy.

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