This guide will be for utility/bruiser Thresh. The build, masteries and runes are the most efficient ones in my opinion

Thresh

Preferred Role:
Support

Thresh is a bruiser support with decent damage, high amounts of CC, and great escape/kiting tools for ADCs. Thresh prefers an aggressive lane and synergies well with strong early game ADCs such as Lucian or Graves. Thresh is vulnerable to getting out-sustained and basically anything that has the ability to block incoming CC.

Read Thresh Lore Here: LORE...

PROS
>High CC
>Escape
>Kiting
>Tanky

Thresh is a good very support overall and is considered to be the best by some. Thresh has a really good skill set. his high amounts of CC capability and his abilities allow allies to catch the enemy easily. Thresh also gives an escape or a re-positioning tool for an ADC without escape, with his Dark Passage. It allows for many pro plays leading to champion kills for you team and assist for you, which will win games. Thresh is pretty bulky thanks to his passive and his scaling abilities.

CONS
>Hard to master
>Sustain
>Poke

Thresh is one of the hardest supports to master,due to every one of his abilities being a skill shot, which makes Thresh a harder champion to use. One of the greatest weaknesses he has is a lack of sustain and his long ability cool-downs. Which also leads to the lack of poke seasonal Thresh players know all to well. Other than your short-ranged auto attacks, You pretty much need to land all of your abilities Pericles and persistently to advance in the game.

I highly recommend using these Masteries, it has two important things which a good Thresh needs, defense and utility. You are tanky enough for the laning phase and you have enough Utility, so you are not behind with the items. I don't really have to explain the points in the Defense Tree because they explain themselves. The Mastery Scavenger will give you 1 Gold everytime your ADC kills a minion. Meditation will give you the Mana you need, so you don't run out of Mana too fast. I've put a point in Inspiration so you don't fall behind in leveling.
The Mastery Culinary Master can help you in very tricky situations or it can help out with the Mana (even if it's not much). Fleet of Foot is a good Mastery on Thresh for chasing or running away. This is the reason why i also like to buy Boots of Mobility. Alchemist reduces the cool down of your Summoner Spells, which is very effective in connection with exhaust. Intelligence is useful in combination with your Death Sentence and all the Items you'll buy. Last but not least the Point Wanderer . This can help you to roam a little bit or for example if an ally is split pushing and the enemy is going to stop him. You will easily walk to your teammate and help him out

Damnation: Pretty good passive actually. This gives a great amount of both ability power and armor. I really value the passive armor gain which basically allows the twice as many magic resist items while still remaining tanky vs AD.
Death Sentence: The ability which makes Thresh a great champion to make a pick-up kill happen. Re-activating this ability actually makes the CC time longer and it's often better to re-activate to close the gap. Don't re-activate if it makes you lose a trade!
Dark Passage: Great escape tool and shield for your ADC, but also great ability to throw at your jungler so the two of you can close the gap together instead of the jungler walking
to the lane.
Flay: Good ability to help with Relic Shield proc since Thresh doesn't get to execute the minion at half hp. It's also great ability to poke enemy support, especially if against melee one. Usage of flay is tricky since it's reversed and when you want to pull enemy towards you, you have to aim behind you.
The Box: Really strong ability to catch several opponents. This can also be used defensively BEFORE enemies get in range to attack you. They're simply forced to go around it or through it. Usually used best when you first land Death Sentence and use it when the enemy is in the middle.

Boots of Mobility are essential for any good Thresh player. If you are thinking of maining Thresh or are even playing him in any ranked game, Boots of Mobility are a NECESSITY. They allow warding around the map to be a much easier process,and allow the ability to roam quicker to other lanes to help carry and win games.
A Sightstone is a must-have item on a Supporter. It allows for clear vision of the map. without vision games are lost as a support it is your job to help with vision placement.Warding can prevent your and the ADC's death.
The Upgraded Sweeper can be really useful if you are playing against champions that can go into stealth, because the sweeper will reveal them. And of course it's very useful for clearing up wards placed by enemies.
The Locket Of The Iron Solari is a very important late game item while it may be a bit expensive, the trade offs are very much so worth it. You gain 10 Cool-down Reduction, 400 Health, 20 Magic Resistance from the locket. you also give a buff to your team with any Nearby allies gaining +20 Magic Resistance and +75% Base Health Regeneration. The Locket also grants you a unique active witch Shield yourself and nearby allied champions for 5 seconds, absorbing up to 50 (+10 per level) damage.
With this build i personally run a sunfirecape it gives you +45 Armor, 450 Health. UNIQUE Passive: Deals 25 + level magic damage per second to nearby enemies. Range: 400.
The Righteous Glory is a very strong item on thresh in my opinion, it grants 650 Health, 300 Mana. Passive: +100% Base Health Regeneration. this will help beef up thresh late game a little. I also use it for the movement speed buffs. The Righteous glory's Active Grants +60% Movement Speed to nearby allies when moving towards enemies or enemy turrets for 3 seconds. After 3 seconds, a shockwave is emitted, slowing nearby enemy champion Movement Speed by 80% for 1 second.
The BF Sword is used for a damage boost and could be built into Infinity edge or Bloodthirster

Flash is the most important spell in the game and is also the most used. It's especially good on Thresh due to the chance to make awesome plays with it. Flash + Dark Passage can also save your teammate a Flash, which is nice. It also makes a great escape or second gap-closer, if needed.

Ignite is the spell that is played by more aggressive supports. Early game. If you are on a smurf account and want to carry hard, or just want some kills early to get your adc fed, Ignite is the spell for you. In the laning phase, it can destroy a carry after a Flay Death Sentence combo. It will get adcs angry sometimes because you "kill steal", but it is important to add that extra damage that changes a burned Flash into a kill.

CLICK HERE IF YOU WANT TO BE A GOOD SUPPORT

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