Now i know this might not sound like a good build but i beg you. Give it a try and see how well you play. I wont be going to much into detail as this is a very simple guide.

Well because they are staight up OP on Twisted Fate. The splash stacks so with four thats about 140% splash, and with the damage you get 303 damage plus crits which also splash. Now this is not the reason i chose them. They are chosen because of the Pick A Card Red Card stacks. Because if you stack your Stacked Deck along with a Red Card your damage output is amazing and you can EASILY 2v1 any squishy and drop any hero.

Not much to talk about here.
Greater Mark of Desolation for the flar armor pen which is needed.
Greater Seal of Armor for the flat armor which is also needed for survivability.
Greater Glyph of Cooldown Reduction because Hey, who doesn't love CDR?
Finally Greater Quintessence of Health Because the HP is desperately needed.

Nothing to talk about here just standard AD Carry masteries. Although feel free to tweak these to your needs.

I chose Ghost and Exhaust because Ghost allows you to get anywhere fast, be it escaping, getting to ganks, this Summoner Spell is amazing. As for Exhaust i chose this because its another slow for when you need to stun with Pick A Card or just to catch that escaping hero.

Early Game: Early game you want to play defensively but be sure to farm because you want to get your Tiamat as fast as you can.

Mid Game: By now you should have Berserker's Greaves as well as two Tiamat and started on your Phantom Dancer. This is when Tiamat TF becomes OP your damage output should be fairly high enough to 1v1 anyone and maybe 2v1 some squishies so farm and gank.

Late Game: Your real time to shine. Hopefully you have finished the build and are now destroying everything. You can backdoor if needed but can be risky, 2v1 every squishy and maybe even 3v1. Just sit in the pack and Red Card and attack and they will all die.

Here is a match i recently played as Tiamat TF.
Enjoy and have fun.