Hi, this is my Xin Zhao guide. It's pretty short but I hope you can use it to carry some games.

Build 1 is pretty much a kill everything hyper-carry Xin. This build works wonders at a lower level of play. Keep in mind you'll be extremely squishy as the build sacrifices some tankiness for maximum damage output.

Build 2 is the more optimal build which compliments your team much better. Bruiser Xin does damage while still being able to take tons of damage. The more optimal build, in my opinion.

For summoner spells I'd recommend taking Flash. Ghost might work too but its just not as good in most cases.

Exhaust and ignite are both nice options. Heal and teleport might work too but I personally don't like using those on Xin Zhao.

I use the same runes for both builds, as those are probably the best runes to use for AD bruisers, regardless of build type.

For carry Xin I use 21/9/0 masteries and for bruiser Xin i use 9/21/0 masteries. Pretty straightforward.

CARRY BUILD 1 (kinda tanky)
Boots of choice
Trinity Force
Bloodthirster
Last Whisper
Guardian Angel
Item of Choice

CARRY BUILD 2 (kill everything don't give a damn)
Boots of choice
Trinity Force
Infinity Edge
Phantom Dancer
Youmoo's Ghostblade
Black Cleaver

Or mix and match. It's up to the player.

Bruiser build items (* = core items):
(early lane game):
Doran's blades (1 or 2) - I'm having a tough time in lane
Heart of gold* - More gold gain. Always nice
Phage* - Just a great item on Xin
Mercury Treads* - AP enemy laner or heavy cc team ... or ... Ninja Tabi - I'm fighting someone like Riven or Darius and they hurt
Wit's End AND Hexdrinker - I'm facing an AP lane (rumble, kennen, vlad, etc.)
Wriggle's Lantern - I'm facing an AD lane (darius, renekton, riven, etc.)
Brutalizer - I'm getting fed and want to snowball

(mid game)
Frozen mallet* - Too squishy, need HP asap
Aegis of Legion - Doing really bad in lane. Going to transition to pure tank.
Youmoo's Ghostblade - If I got a brutalizer earlier
Randuins* - There's a lot of teamfights going on, and I need armor ... or ... Frozen Heart -Someone on my team is already getting randuins and we don't have a frozen heart yet

(late game)
Maw of Malmortius - Built a hexdrinker earlier. Gonna finish it now for more damage
Guardian Angel - I'm doing a ton of damage and everyone is focusing me
Force of Nature - Enemy team has 3 fed Ap carries lol
Bloodthister* - Not doing any damage ... or ... Black Cleaver - We have a lot of AD on our team ... OR ... Last Whisper - Enemy is straight up stacking armor
Ionic Spark - Split push king (only if you took teleport)

-Xin is extremely powerful at early levels. His 3 talon strike does a surprising amount of burst damage
-Your ult is extremely useful in teamfights. You can use it to initiate or keep it to knock away champions like Kennen or Fiddlesticks
-If you want to set up a gank, dash to a minion behind your enemy and knock them towards your tower with your ult
-If not doing so well, transition to a support tank build instead of a carry build. GP5s are great if you are being zoned out.