I have taken inspiration from ALL THE BEST Xin Zhao players and am combining those DIFFERENT PLAYSTYLES to make you adapt to any Matchup/Game thrown at you.

My Main Inspirations are:

1. 1vsAll (1300+LP Challenger & Korean Youtuber/Streamer uses Xin Zhao as Counterpick not OTP)
   (Credited for the Conqueror Setup vs ranged & weak laners)
2. 
   XoraV1 (1200LP peak Brazilian Challenger OTP)
   (Credited for the Conqueror Setup vs harder lanes)
3. kenono #EUW (800LP Challenger Trinity Force/Crit Xin Top OTP )
4. SenKiya#NA1 (950+ LP Grandmaster OTP)
   (Credited for the Grasp of the Undying / Tank Setup for harder Matchups)
5. Pleutre#Lol ( 300LP Master without banning anything EUW Xin Top OTP Streamer/Youtuber)
   (Similar Tanky/Safe and very FLEXIBLE setup rushing Titanic Hydra)
   

2 Main Setups
1. Aggro Setup ( Eclipse/ Trinity Force builds) often using Ignite + Doran's Blade
(vs most Champs, like Yone, Jayce, Rumble, Kayle, Gnar, Aurora, Gangplank, Smolder, Darius)

2. Tanky/Safe Setup ( Titanic Hydra builds) (vs Champs you can only beat through sustain, like Camille, Sett, Kled, Garen, Illaoi, ALL TANKS)

When to pick XinZhao Toplane:
Overall Xin likes 4 types of enemies
(Look for these types of champs in the enemy team Im not rating the lane here):
1. Enchanters: Xin Zhao like to play both WITH Enchanters AND AGAINST them!! Sona, Soraka, Seraphine, Lulu, Nami, Renata Glasc
2. Squishy/Oneshottable non-Statchecking Melees (So champs like Rengar, Yone, Yasuo, Akali, Sylas, Riven, Zed
3. Mid-Low CC or Mid-Low Peel Tank champions: i.e. Sion, Ornn, Zac
4. AP Champs as Xin Zhao really likes RUSHING Maw of Malmortius (Insane if they have 2 AP Top JNGL)
5. Multiple Ranged Champs in Enemy Top/Mid/Jngl as Xin Zhao gets increase value out of Audacious Charge & Crescent Guard and Xin Zhao really likes building Stridebreaker giving him insane sticking potential

When not to pick Xin Toplane:
1. You have 0 Engage/Followup team, who only want to poke/run away/get run into i.e. Heimerdinger, Janna, Kindred, Zyra
You dont want to be the sole primary engage so look for skirmish heavy allies!
2. Enemies have high Disengage/Counter-Engage Champs ( Janna, Thresh, Poppy, Gragas, etc.) or high lockdown cc i.e. Leona, Alistar, Rell, Skarner
3. Melee Statcheckers, because Xin thrives if he can jump in and actually win the duel, champs like Darius, Garen, Volibear, Nasus, Sett want you to run into them and are too tanky to kill quickly
4. other Champs Xin doesnt like playing against: Amumu, Annie, Lillia

Xins Items are quite flexible and dependant on enemy top&jngl, runes & gamestate:

Starting Items:

• Doran's Blade: If dueling power is needed, scales better (often paired with Ignite & full damage build)
• Doran's Ring: For better Health and Mana sustain, better shorttrades, better vs Tanks (often paired with TP and scaling Titanic Rush builds)

Boots Options:
Boots of Swiftness are really underrated
otherwise Mercury's Treads or Plated Steelcaps are good


Default Rush:

• Eclipse: Generally the most flexible Rush Item for Xin. In many matchups like Darius you cant afford to wait till you can afford Trinity Force (433g more than Eclipse) + being forced to buy awkard and inefficient components like Hearthbound Axe and Sheen can make you lose lane hard. This is where you rush Eclipse with Magical Footwear and Cosmic Insight which gives more uses of Flash Ignite Eclipse and Titanic Hydra REALLY OP!
  Eclipse is also more flexible than Trinity Force since it can either be followed up by Black Cleaver and Titanic Hydra for a bruisery low Cooldown build or by The Collector and Mortal Reminder / Lord Dominik's Regards for a high dmg crit build.
  The Bruiser build is the standard option for most top matchups!
  You prefer crit in certain matchups like Aatrox where you need the extra damage to kill them quick or else they will outheal you or if enemies have lots of squishy champs!
  If you are really far ahead i suggest not going crit as the Bruiser build is less risky

• Trinity Force: Best if you wanna go FULL Damage build. Compared to Eclipse it gives more All-In Statcheck Power, while Eclipse requires more weaving in and out when fighting bruisers, waiting for cooldowns and Eclipse procs
  Trinity Force scales better, especially once you get some Crit items like The Collector or Lord Dominik's Regards which is why you want to run it into champs where you win early anyways but need to match their scaling like Garen, gives movespeed which is always nice, works super well with Jack of all Trades, similar huge completion spike to Eclipse though it is slightly more expensive

• Titanic Hydra: Default Rush for Safe Scaling build! or Anti-Tank Build!
  Opens up proxying possibilities with early Tiamat, You can get to other HP-Synergy items quickly
  More about the 2 builds!

Other Rush Options (Situational)

• Maw of Malmortius: MUST BUY vs most AP champs or even better when vs 2 Magic Dmg Champs Top & Jngl. Great Scaling, The Omnivamp is INSANE in teamfights and Skirmishes!!
  
• Essence Reaver: Only buy when you are snowballing!! Similar/higher dmg to Eclipse/ Trinity Force, Only buy when youre winning lane hard and dont need Triforce Spike 1v1 Power, Damage scales great because your W Wind Becomes Lightning scales with Critical Strike Chance, Lets you stay in lane forever with 0 Mana - Problems
  
• Black Cleaver: Good vs high Armor stacking Tank ( K'Sante especially)

"Outdated"

• Sundered Sky: Used to be most flexible Option for Grasp of the Undying scaling/sustain HP-Synergy build, either followed by HP-Synergy items or damage items, makes you really tanky and scales well with your high Health from Health Scaling, Overgrowth & Items, Good at short Trades in Lane, Godlike in skirmishes, especially good vs teams where you can proc it multiple times
  
  The main problem with this item (only for lane) is that it delays other essentials for Xin too much like Armor Penetration with Black Cleaver & Lord Dominik's Regards, Waveclear with Titanic Hydra,
  

Any other items like Stridebreaker OR Blade of the Ruined King are either too expensive/too low damage/too squishy and usually are WAY better as second Item!!!

Other:
Warden's Mail + Plated Steelcaps: Can completely ruin some laners like Tryndamere, Kled

Tear of the Goddess: Good vs some Tanks, means you can start Doran's Blade instead of Doran's Ring and not have huge Mana Problems vs Tanks. Only good if you dont need the 1v1 power and want to have a big scaling option with Muramana for later (One of the best builds for below Emerald)

Stridebreaker: Works really well if youre vs many ranged enemies and winning lane hard early!! Pairs well with Muramana for a pretty slow build with an INSANE!!! 2 item spike once Muramana is stacked,
Its only not used as much because it gives too little dueling power for such an expensive first Item + Swifties give the same great combatmobility for just 900g

Blade of the Ruined King: Good vs multiple (2-3+) high HP Targets ( Sion, Dr. Mundo), ONLY if Black Cleaver is not needed, such as you being on full AD Team or vs ultra Armor stackers like K'Sante, Malphite)

Aggro/Damage Setup:
Building high Damage on Xin is VERY valuable as your Ult makes you artificially tanky, the goal is to be able to oneshot squishies then ult to walk out or keep killing

Playstyle:
XinZhao is really good against most Marksmen (ranged) champions or weak lane champions that cant deal with someone jumping on them.
Against those weak duelists you should play aggressive lv.1, with an E ( Audacious Charge) All-In at lv.1.
Be careful not to jump into too big waves like either full untouched lv.1 wave or the second wave right as it arrives! Those things will make you lose even against weaker enemies.
Against some enemies if you got a really good lv.1 trade you can skill Q lv.2 and look for the kill, otherwise if your not confident it will be enough fo for W lv.2

In many other matchups, especially against melees you tend to not win the lv.1 E All-In and should instead start W Wind Becomes Lightning. I recommend playing for wave priority, trading with AA->W->AA, which lets you win short trades against most champions.

From lv.3 onwards you should trade against weak duelists/ranged with your combo E->AA->Q->W (VERY FAST BURST COMBO), then either chase them down for kill OR back away -> wait until your Q is about to expire -> AA a minion -> YOUR E will BARELY come off cooldown as your Q3 is about to expire -> Jump on them or Flash Knockup and follow with E if they flash away
(look at Combo section for example)

Against stronger duelists you can E->AA->W->AA->Q->Q->Q->W for the quickest way to get your W back in combat.

In general even if you just get an equal health trade, Xins INCREDIBLE SUSTAIN from Determination means those trades are benefitial to you.

Thats also why Ignite is so MANDITORY especially in ranged matchups, because it means you often get uncontested access to the wave (because the enemy is scared) letting you heal up.

Xin Zhao becomes really strong around lv.4-5 when you get some points into W Wind Becomes Lightning and can freeze the wave after having recalled.
Then your next big spikes are lv.9 for fully maxed W Wind Becomes Lightning and Eclipse giving you GREATLY IMPROVED short trades (see Matchup section for specifics)

Build:

You go Doran's Blade most matchups, often buy Executioner's Calling early if they have any healing
VS AP Champs you (almost always) buy Hexdrinker -> Maw of Malmortius ESPECIALLY if the enemy jungler is AP aswell, which lets you beat 95% of AP Champs in the 1v1 easily

The big decision is whether to go Eclipse or Trinity Force
For more info go here

Runes for both Eclipse Builds:
Conqueror, Triumph, Legend: Alacrity, Cosmic Insight, Magical Footwear, Attack Speed, Adaptive Force, Flat Health (for maximum early stats)

1. Eclipse Bruiser build:
Eclipse -> Black Cleaver/ Titanic Hydra -> Titanic Hydra/ Black Cleaver -> situational

This build is the default

2. Eclipse Crit build:
Eclipse -> The Collector -> Mortal Reminder/ Lord Dominik's Regards -> situational

Good vs specific matchups like Aatrox or vs squishy enemy comps

3. Trinity Force Crit build:
Conqueror Triumph, Legend: Alacrity, Jack of all Trades, Biscuit Delivery, Attack Speed, Adaptive Force, Health Scaling
Trinity Force -> Mortal Reminder/ Lord Dominik's Regards/ The Collector -> situational

Best scaling and highest dps/statcheck build

Best Situational Items:
Maw of Malmortius, Death's Dance, Edge of Night, Serpent's Fang, Immortal Shieldbow, Sterak's Gage, Wit's End

Safe/Tanky Titanic Rush Setups
These Setups can turn horrible matchups into winning matchups

General Playstyle:
This "Safe" Setup is focused on SHORT TRADES and ABUSING SUSTAIN from XinZhaos passive Determination and Runes.
Doing this you slowly widdle down stronger earlygame champs letting you win otherwise unplayable matchups.
This build is GREAT VS Camille, Sett, Kled, Illaoi or any Tank)
This build SUCKS vs champs that can run you down or where you need dueling/statcheck power: Darius, Trundle, RANGED CHAMPS)

Builds:
These builds are defined by RUSHING Tiamat into Titanic Hydra which is already one of Xin Zhao's best items because of its interactions with Three Talon Strike

Both of these builds are very high HP builds which is why they work best if the enemies have LOW %-HP DMG

Most games you go Doran's Ring (Increasing your Determination Heal and fixing your Mana issues with Presence of Mind)

1. Safe Scaling Build:
Conqueror, Presence of Mind, Legend: Haste, Last Stand, Second Wind / Bone Plating, Overgrowth

Insane 2 & 3 Item Spike with Titanic Hydra -> Black Cleaver -> Riftmaker, Finishing build options: Unending Despair, Jak'Sho, The Protean, Spirit Visage

2. Anti Tank Tank build: (usually with Ignite)
Grasp of the Undying, Demolish, Second Wind, Overgrowth, Presence of Mind, Legend: Alacrity
Shards: Attack Speed, Health Scaling, Health Scaling

Boots of Swiftness or Tiamat Rush -> Titanic Hydra -> Hullbreaker -> Speed Tanks items like Dead Man's Plate, Force of Nature, Jak'Sho, The Protean

Many Tanks cant deal with high HP stacking and you can practically ignore them with this build, going for constant Demolish and Hullbreaker procs while proxying the wave and sustaining up

Laning/Trade Combos:

(prepping your passive if you are going for a trade helps, as it gives bonus dmg)

Main Quick Trade Combo: E->AA->Q->W (followed by extending or disengaging), with this combo your E and W will be on a similar cooldown and once you get some levels you can stall your Q autos out so you fully reset you E and then reengage Play Video
All-In/Full commit Combo: E->AA->W->AA->Q->Q->Q->AA(wait for W)->W or starting melee: AA->W->AA->Q->E(somewhere here)->Q->Q->AA(wait for W)->W
This combo gives highest W CD reduction and best for if the enemy will fight back. Once you have enough CDR 3 Qs fully reset your W giving you 2 quick Ws Play Video
Q Prep Combo: Q Minions twice->E->AA(Knockup)->W
(this combo is often used to tower dive! There are better combos for trading!!)
Q Minions Twice -> Flash -> knockup -> W -> AA+Ignite is often better to surprise finish opponents off, especially if you just used E Play Video
Longrange Engage with W->E (Usually only good if you are coming from the front, If you are flanking the enemy team (which you should) you probably wanna engage with E or R->Flash)

Followup/Delayed W Combo (highest damage (useful) combo for lane) W->Wait2Sec->E->AA->Q->Q->Q->W Play Video
W -> Flash -> E for super longrange W or repositioning a missing W Play Video

Crescent Guard Ult Combos:

(in general your ult does Current HP dmg, so it does more if they are higher HP, If you know that you want to fight someone to the death 1v1 you might wanna use it earlier rather than later, this ofc has tradeoffs like more ppl coming or disengaging and using it for turret dive combos etc.)

R->W is really fast so the full main damage combo can fit in R for maximum damage Play Video Full Fast Max Damage Combos: E->AA->Q->R->W or long Combo: W->Wait2Sec->E->AA->Q->R->Q->Q->W Play Video
E->R mid-dash especially good when diving for maximum burst as you skip the R animation Play Video
You can R->Flash into many people in teamfights, this pairs especially well if you R->Flash->W->E or R->Flash->E Play Video
Can be combined with Q-Prep for the "Pleute Special" for ultimate towerdiving combo
Q minion twice -> R -> Flash -> E -> Q3 -> W
Play Video
You can R someone into a Wall to stun them without knocking them back far. This is especially useful when towerdiving in toplane letting you R(into Wall)->W hitting both parts of your W while they cant react letting you followup with E if they flash afterwards Play Video

Ult Insecs:

Unreliable Variation: E -> Flash behind enemy (so E doesnt mark enemy as challenged)-> Ult Play Video
Improved Xinsec: E -> W (hitting a second enemy) -> R -> Flash behind primary target Play Video

Avoiding Jungle Ganks by getting deep Stealth Ward in the enemy jungle is one of the most important tips to help you climb as Xin Top! Especially getting a sneaky ward onto enemy Buff lv.1 lets you predict where they will path towards, and if you think about their whereabout you can often tack which side of the map the enemy jungler will be on, helping not only yourself but your team!

Disclaimer: All of the above information isnt my own but merely the result of lots of research, personal questioning and translating already existing scattered information from the best Xin Zhao Top players.

As for myself i will update my personal climbing progress here:

1. I never played much Ranked in the past and only became interested in climbing seriously 2 seasons ago. Back then I was playing only (old) Skarner Top and some occasional Kled. After watching lots of high Elo players i found my love for Nocturne, Sejuani and Xin Zhao Toplane


2. Last season i managed to hit Diamond with 76% WR with less than 40 games, but couldnt play more because of work, sport and personal reasons (girlfriend)