Talon is very (x1,000,000) squishy. That is the first thing I say cause it is his downfall. Some say he is the best as a burst, I say, build him as a hybrid carry/burst. His passive works well with frozen mallet, it will allow you to get more damage as well as build for survivability. COOLDOWNS ARE VERY BAD. Your skills have a long *** cooldown except for your (Q). This is why frozen heart is very good plus it builds for survivability. Also your ultimate is amazing as it lets you get into the middle of the fight while being conceiled. This allows you to get the full potential of frozen heart's passive. Youmuu is amazing as it gives you crit chance AND cdr. Infinity's edge is your main damage source. It will allow you to be effective when autoattacking and bursting. For the other 2 item spots it is purely situational.

Build attack speed as you are lacking it now. Phantom dancer will allow your crit chance however will leave you less sustainable. You probably WILL last all teamfights as you have great escape techniques such as ghost and shadow assault combo. This is why Stark's fervor is also a good choice. It will allow you to counter thornmail on carrys. For boots you have to make a choice between MORE attack speed or tenacity to help your tankyness. The boots all depend on the enemy composition, more cc champs or less. Movement speed is no problem so dont worry about chasing, you have great chasing skills. Thornmail is useless as you won't be targeted long enough for the effectiveness of thornmail, plus its easily countered and you have frozen heart already!

Get in the fight, stealth, then target a carry. Your items have unique passives that will benefit the team as a whole so the stealth will allow your survivability. Dont be worried if you can kill them or not, your blades will take them down to about half health, the rest is up to your passive, frozen mallet, 50% crits (or more if you build phantom dancer), (Q) spell. If you use your skills correctly, the enemy carry will not even know they are being targeted cause of incredible bursts and stealth. Your ulitmate will also cause chaos as now the blades become traps for the enemy to avoid when stealthed from your ult. You are not very reliant to your tank so independently kill the carrys as quick as possible. KILL CARRYS, THAT IS YOUR ROLE! If you fail, say bye to your teamfight. Dont attack tanks, they are not your problem, SQUISHY CARRYS ARE! Remember you are a high risk, high reward champ, do your duty.

Early game you suck at farming, so harass with your blades. Gank mid whenever he/she overextends. Blink first, then use exhaust, then spam (Q), then auto attack to death! If they look like they might be able to escape, your (W) will wittle their health as well as slowing them. Last hit minions/champs with your (W).

Mid game you will have your ult, ganking will be too easy. Just use your ult whenever you think stealth is appropriate as well as a quick burst.

Late Game take them towers down as you are also a hybrid carry. TARGET SQUISHY CARRYS IN TEAMFIGHTS!

Dorans blade is nice to start off with, then avarice blade (early gold gain), boots (merc or berz), then Youmuu's, Mallet or Frozen Heart it all depends on you, INFINITY's EDGE!, attack speed item (starks or phantom), either frozen heart or mallet (the other one you didnt choose).

Build as above except choose between desolation or furor quint, I personally choose furor as my Youmuu gives me good armor pen and so does my marks already.

Swap ignite or exhaust if you want. I personally choose exhaust cause your auto attacks will do a lot of damage plus it helps land your (Q) spell more often. Flash is cool for better escaping but I like ghost more as it can be either offensive or defensive. Plus you already have a gap closer spell anyways. Stealth is already a good escape tool too.