This is my first guide in mobafire so i dunno how to edit most stuff in here, be patient, ill get it with time. i selected twisted fate as the champion for the guide, i'm playing him a lot and so far this build never failed me, and TF is one of the best assassins in the game, with a right timing and good positioning, you can go legendary the blink of an eye ;]

i go with armor penetration marks and quints, they're great early game and they have an awesome sinergy with sword of the divine andthe black cleaver, making the opponents hp drop like water, and off course the most usual runes for dps champions.

for seals i choose attack speed, hitting fast is something u must do with TF, since the extra damage is only dealt in your 4th attack, and the earlier u get the black cleaver stacks on, better, TF stun lasts 2 secs, u might wanna deal the highest amount of damage possible in that time.

and for glypths i go with magic resist/lvl, provides a little defence against casters, since ur not supposed to engage meele dps directly, that will give you some survivability in the game.

i go 21-0-9
the 21 points in offense are pretty much a must, i dont like going 21-9-0 just to get some armor, i rather have the bonuses from the mana and life regen, and make my ghost spell a little more efficient.

Flash ang ghost are my favorite spells for DPS ranged champions, but you may also go with ignite or exhaust, any other spell besides theese four are just a waste IMO.

with flash and ghost u can get in and out of combat pretty quickly, using ur "W" to help you in the process, many many times i've escaped ganks using TF W and one or both of theese skills.

in the early game i try to rush the sword of the divine, this iten just fits TF perfectly, boosting his damage on each 4th hit, and providing him attack speed and more armor pen, after that u want your black cleaver, combined with the sword and your runes, you get more than 100 armor pen, which usually will result on doing extra damage to many chmapions, after theese two itens are done you go for the IE, TF critical damage should be something like 600, followed by the bloodthirster, and a phantom dancer, if you want to after buying the first dancer, you can sell the boots to make another one, u'll have enought move speed and will have a huge chance of critical and attack speed on each hit.

Pros

-Awesome ganker.
his ultimate makes ganking amazing, u can simply chose where u want to be, in a team fight, and hunting lone champions is pretty easy with twisted fate.

-Provides Map awereness.
his ultimate can be very good in the late game, when each team walks in packs, you can provide your team with vision of the opposing team in order to avoid ganks, or even better, to make your own gank, and of course check their positions.

-Good farmer.
twisted fate can farm pretty well with auto attacks or his skills, i usually just use the right timing to farm in early game, and use the red card to handle lots of minions, and his passive gives you 2 extra gold/unit killed, this may seem irrelevant, but how many times u headed back to the fountain and were missing like 20 gold to buy that BF sword? TF avoids this kinda stuff.

-Teleport.
wait? teleport? where to? the whole MAP? AWESOME!

-3 Great effects in one skill (stun/slow/mana).
his skill "pick a card" is veeeeeeery usefull, when activated a random colored card will show up on TF head, and it will change color in this order BLUE-RED-YELLOW-BLUE, always in that order,if you press W again, you'll get the selected card, and your next attack haves an aditional effect, now how you use each card...

BLUE
The blue card deals an extra amount of damage (the highest one among the colors) and gives u 65% of the damage dealt in mana, try to use this on creeps whenever possible, the spell pays for itself, so you'll only be gaining mana and dealing extra damage, pretty good huh? althought not so good in teamfights or ganks ;/

RED
the Red card deals an extra damage, and hits nearby enemies as well, slowing them for 2 secs, i usually use this card when there's a big amount od minions on a lane, or to hit an enemy behind minions, because you wont be able to hit them directly everytime, pretty usefull for escaping multiple enemies.

YELLOW
Ahá! here's your money maker, this is the card that makes enemies run when they see it on Twisted fate's head, the yellow card deals an small amount of extra damage, but stuns the opponents for 2 secs, which usually is enought for you to grind their HP, this is your kill tool on a gank, and my favorite card by far.

*REMINDER* some people may not know but u can use (and you should), always use ur W before teleporting to gank someone, that way u'll get there with the stun/slow ready, getting the right card can prove a little tricky task, but with time, you won't miss it anymore.

-Back door/taking turrets down
sometimes your opponents are busy chasing that rammus on your team that never dies, and meanwhile a group of ur minions is near a turret with no near champion, using TF ult u ca check if its safe and go break the turret into pieces very quickly, and by many times doing BD is possible with tf, i've won some lost games many times, when the opponent was destroying our base, i just ulted to their, and broke the nexus while my team protected ours.

-he's gambit's cousin (Y).
What? u guys didn't noticed? Ò_Ó

Cons
-kinda squishy.
twisted fate can deal an enormous amount of damage, yes, but hes very squishy, so you need to be very well positioned in a team fight, because usually you'll be focused, and one more thing, before ganking someone by yourself, make sure to be certain that u'll KILL it by urself, otherwise dont go feed.

-dances weird.
really, what the heck is that?

-a good timing is needed to play him properly.
like i said "pick a card" can prove to be tricky, sometimes when ur fleeing from an enemy u'll need to think fast and don't miss in order to get the kill/stay alive, an using the teleport properly as well, the teleport takes 2 secs to work, so u'll need to predict your opponnents movement in order to make ur gank succesfull.

the skill is very good indeed, but the damage is nearly irrelevant if your not playing TF AP, yes it can finish off fleeing enemies, yes can deal good damage on waves of minions, but no, if you play it correctly you wont miss it, it is a must have skill in AP builds, in AD? nah IMO.

thank you guys for reading the guide, i hope it is usefull, and i'll be looking foward to make better ones, and to keep this one updated, any suggestions os complaints are welcome, and if ur giving me thumbs down, leave a comment on why, i would love to improve!
cya folks ;P