Hey guys! This is WitsEnd. This is a guide that'll help you learn the basics (and hopefully the more advanced details) of Xin Zhao. Xin is one of the easiest and strongest junglers to play, even after his recent nerf. He has sustain, crowd control on each of his spells, mobility, and survivability: some of the main criteria for a good jungler. Although there are many possible builds for him, I will only be going over one of them: the standard Xin Zhao build that I prefer in most matchups. I hope you enjoy this guide!

Pros

High CC
Good mobility
Good damage output
Decent survivability
Good clear
Straightforward kit

Cons

Weak in late game
Weak sustain in jungle
Easily countered
Conditional jump: no escape
Gets outscaled

Your skill priority should be R>W>Q>E.

Passive Every 3rd basic attack or Wind Becomes Lightning deals an additional 15/25/35/45% (based on level) physical damage and restores 8-59 health (+10% AD and 40% AP). A good source of jungling sustain, this makes Xin Zhao good in drawn-out fights.
Wind Becomes Lightning Xin Zhaoo performs two attacks over .5/.4 (based on AS) seconds, each dealing 30/40/50/60/70 (+30% AD) damage. The first strike strikes in an arc, and the second strike hits forward in a line, slowing enemies by 50%. Strikes deal half damage against minions, benefit from 1/3 of Xin's lifesteal, and pause all effects of his other abilities while active. The first skill you should max, Xin's W is your main source of damage, best camp clear, and provides good CC. Kite raptor and wolf camps in a line so that you can use your Wind Becomes Lightning effectively, striking the first enemies with your arc and the remainder with your slash. Spell shields block only one of the attacks- either the thrust of the slash.
Three Talon Strike For the next three seconds, each basic attack deals additional 20/25/30/35/40 +40% AD bonus damage and reduce the cooldowns of other abilities by one second. The third basic attack also knocks up the target for .75 seconds. Casting this spell resets your auto attack timer. One of Xin's biggest sources of crowd control, your Q should be maxed second after Wind Becomes Lightning. Empowering your auto attacks and knocking up enemies is a huge tool on Xin Zhao. Additionally, this skill reduces the cooldowns of your other spells- so time this wisely in the jungle. Three Talon Strike has no cast time and does not interrupt your other spellcasts. Cooldown begins only after duration ends or all three attacks are completed.
Audacious Charge Dash to a target enemy, dealing 50/75/100/125/150 +60% AP magic damage to all nearby enemies, slowing them for 50% for .5 seconds, and gaining 40/45/50/55/60% attack speed for 5 seconds. Providing Xin Zhao with attack speed, mobility, and crowd control, your E is the last skill you should max. Although all of Xin's spells are very important to his kit, this one has the least synergy and maxing it is the least important. This is your gap-closer- it is a great tool for ganks and engages.
Crescent Guard Passive: the last enemy targeted by basic attacks or Audacious Charge is challenged for 3 seconds. Sweep around yourself, dealing 75/175/275 +100% AD +15% of target's current health as physical damage. Damage against monsters is capped at 600+100% AD. All non-challenged enemies are knocked back to 450 units away from Xin Zhao and stunned for the duration that they were knocked back for. For the next 3 seconds, become invulnerable to champions more than 450 units away from him. Basic attacks and spells extend the duration by .3 seconds, but the remaining duration cannot excede 3 seconds. A great defensive ultimate spell, this is a solid group-fighting ult. Creating a zone where Xin Zhao is immune to damage and knocking unengaged enemies back, this spell provides great utility and should be used both offensively and defensively. Additionally, staying in combat will extend the duration of the spell, making you essentially invincible in group fights. DoT damage will not damage you if the source is outside of the cast radius. Minions, monsters, and towers will still damage you even if they are outside of the zone. Crescent Guard does not negate crowd control effects outside of the zone, but it does negate the damage.
At level 3 you should take Audacious Charge. This is your gap-closer. Although it scales with AP making it a less viable damage-dealer, simply jumping at your opponent and slowing them, and setting up a strong burst W-Q combo is a great start for a successful gank. Skilling Audacious Charge early on allows you to clear well early on and pull off good ganks early in the game when you see opportunities. However, don't be tempted to max Audacious Charge first. Although it slows enemies and grants you attack speed, it scales with AP, and the extra utility is just isn't worth in comparison with the damage increase on the rest of your skills.

The fact that Xin Zhao gets his power-spike at level 3 makes him one of the strongest early junglers in the game. Getting an early kill puts him at an experience lead and a gold lead against the opposing jungler.

Take Flash and Smite for your summoners. There are very few junglers who can afford to not take smite because of their amazing clear and sustain, and Xin Zhao is not one of them.
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Xin Zhao is a duelist. The runes you take on him should both strengthen his strong points and make up for his weak points.

Primary Runes

The best keystone for almost every duelist jungler. It will easily proc from Xin's combo, and it will increase both your damage and your laner's damage during a gank.
This is a great rune for group fights or even 1v2 situations. The additional gold also adds up.
Who doesn't want extra attack speed?
A staple rune for precision trees, this is a great rune for a jungle. Being able to set up great ganks against low-health enemy laners with this rune is very important.

Secondary Runes

This rune skyrockets Xin's duelist potential and makes him a bit more tanky, allowing him to build offensive items while still remaining beefy.
Similar to Bone Plating this is a great duelist and sustain rune.

Alternative Options

Domination allows you to take a more offensive turn on Xin Zhao. This rune provides for some solid burst damage in addition to his regular combo.
This solid source of mobility is a nice offensive and defensive option.

At the start of the game, buy Hunter's Machete and Refillable Potion. Generally, my favorite clear path is blue - gromp - wolves - red - raptors - closest scuddler - krugs. Don't be afraid of the camps, your passive won't let you die.

After clearing in this order you're level 5 and are ready to gank and potentially rush an early drag. Rush drag if any of the following is true: 1. the enemy jungler is dead or ganking top, 2. you have both bot and mid/top helping you, 3. your bot lane is ahead and/or the enemy botlaners are dead.

Early on, if you're against a weaker team composition, you might want to invade. More often than not it'll be worth it because of Xin's early game strength. At 10 minutes, you should be aiming at 50-60 CS (and throughout the game 5-6 CS per minute is just great), two-three kills/assists, and a drag.

During your first back, buy Skirmisher's Sabre and then upgrade to Skirmisher's Sabre - Bloodrazor. If you don't have quite enough to upgrade, buy boots. My favorite boots are Ninja Tabi but Mercury's Treads are better in some matchups. The next big item to build is Trinity Force. More on items later.

At level 4 you'll be able to start pulling off successful ganks. Generally, just wander around and freefarm, but when you see someone at low health, try to get a kill off on them. Get your team to communicate with you- if they need help they should ping, and you should finish clearing and come down to help.

During a gank, if the enemy is pushed in, just walk up to them and W into Q. Do not E onto them unless they blow their escape: it will help secure a kill. However, if the lanes are even, you will want to E onto them and then fully combo. Likely you will burn a Flash and ganks will be much easier after that.

Middle game is where Xin Zhao is best. After establishing pressure and dominance in early game, Xin is able to snowball hard into mid to late game. The best things to do as a jungler in middle game is roam, take enemy jungle camps, and look for enemies caught out alone. Because of Xin's dueling abilities, no enemy is a problem. Catch out split-pushers and free farmers, and feel free to invade the enemy jungle, just be careful that the whole enemy team doesn't collapse on you. After level 7 you can solo dragon easily, and after level 8 feel free to take out Herald if any of the following are true: 1. You have top scuddler, 2. Top is pushed in hard, 3. Both mid and top are helping, or 4. The enemy jungler is dead. Herald is a huge tool: it gives you pretty much a free tower or inhib. It makes me sad that so many junglers neglect it.

If a group fight breaks out, run in. Don't worry if you die. You're the not-so-tanky engager, and your job is to run in and start the fight. E onto the enemy carry, then faceroll and try to take them out. Your ultimate Crescent Guard is an amazing ability for group fights. It can be used both as an execute and as a defensive ability: It does damage to enemies based on their missing health and knocks back enemies who you haven't engaged. Use this if you or the enemy carry are low on health- it can save your life in group fights.

Unfortunately, Xin Zhao falls off a little bit late game. However, because of his early game strength, most games won't last longer than 30 minutes and you don't ever finish your full build. In late game just try to continue what you have been doing in mid game, but try to get objectives more often and stay with your team rather than split-pushing and picking off enemies.

My favorite building strategy on Xin Zhao is buying your core items and then finishing up with counterbuilds. Most games with Xin Zhao are so short that I never get a chance to complete my build. However, I always know what I am going to build in case the game drags on for a long time.

I prefer Skirmisher's Sabre - Bloodrazor over Skirmisher's Sabre - Warrior on Xin Zhao. Although a lost of people prefer Warrior, I take Bloodrazor because Xin Zhao gains passive AD and gets CDR on his Q. The choice is ultimately yours.
Similarly to a lot of top-lane bruisers, you should build Trinity Force early on. Strengthening your combo and providing a strong balance of stats boosts, this is a core early game item providing for a nice powerspike.
Even more CC! I like to build Frozen Mallet early on because it strengthen's Xin's CC to a mad amount and provides him with both tankiness and damage.
Although not a core item, this provides solid survivability and split-pushing/clearing potential. Even if you never upgrade, however, building Tiamat in early game is necessary.
Giving some nice armor and health boosts along with mobility, this is a nice offensive tank item. I often build this around late-game if the enemy carries are scaling hard.
This provides both good AD and MR. I build this very often against very bursty enemy mages like Veigar or Katarina. I often build this as a core item anyway, just because of its offensive potential.
If you're lacking offensively, you should start building ADC items. This is the single strongest powerspike item in the game, and should be a nice start if you want to deal more damage.
This item gives a nice combination of AP and AD, and is very strong on Xin Zhao in both the early and the late game. A great offensive item, if your enemy is not doing much damage this is a core item to build.
BotRK is a great offensively balanced item to build on almost any champion. With a boost in LS, AD, and AS, this is a solid offensive tank-shredding item to build.
If you are the only peel/engage champion on your team, build this item, otherwise you will be dying in every group fight after the engage. This item gives you a nice second-chance in close duels or a clutch win in hard group fights.

Thanks for reading my guide to Xin Zhao! I hoped it helped. Good luck playing him, and I hope you have as much fun playing him as I do.