One thing to decide before you pick a build; "What kind of Thresh do I enjoy playing?" There are many ways to play Thresh; Full Tank, Bruiser, DPS, Hybrid Healer, and Peel (just to name a few).

I personally enjoy playing him Full Tank, and Healer depending on my teams composition.

I break down the play styles into 3 groups. Engage (Agressive), Zone (Pressure), and Peel (Passive/Escape).

-To play Aggressive you need to be very good at predicting where your enemies will move to and catch them with your Q.
-To play Zone, you need to be able to recognize when the enemy is trying to engage or escape and lock them down with your Q or E.
-To play Peel you need to be able to develop a 6th sense for when your lantern will be most useful in keeping your ADC alive.

The big thing with runes is picking runes that BUFF your champion's natural abilities and the items you intend to use. Example; on support champions Ingenious Hunter is an amazing rune because it lowers the cooldowns of both your Vision Trinket and your Support Items (Redemption, Mikael's, etc.).

On thresh, there is one rune that you MUST take. Conditioning. Your passive builds Armor for you as you pick up the souls of your enemies, so having your armor buffed by a rune makes you a much harder target to take down.

As for Keystones, that depends on your style.
For Agressive style, take Aftershock or Electrocute. This will make you either incredibly tanky upon engaging, or deal a burst of damage that will help your ADC secure the kill.
For Zone style, take Aftershock/Guardian or Summon Aery. This will allow you to be a front line for your ADC and provide them with additional shielding when they need it most.
For Peel style, take Guardian or Summon Aery. This makes sure that you have that extra Shield to keep your ADC safe, even when they get caught out.

Remember, take runes that buff YOUR STYLE.

My favorite runes for Thresh are in the Resolve tree. Use either Aftershock or Guardian for your Keystone, depending on your play-style.

-Font of Life: when you land your Q, E, or R onto an enemy champion, your ADC can then Heal themselves by attacking that champion. This pairs well with the item Knights Vow.
-Conditioning: this buffs the Magic resist from items and the Armor from both your passive and your items.
-Overgrowth: Thresh does not have a lot of base HP so i like to scale up as the game goes on.
-Revitalize: If you don't want to take Overgrowth, having a more powerful shield is always a good idea.

Any champion can be a scaling champ... I repeat; ANY CHAMPION CAN BE A SCALING CHAMPION!!

There are two ways to do this; Transcendence and Gathering Storm.

These work especially well on Thresh becaus, as a support you are building Cooldown Reduction that is built into all your items. And Gathering Storm gives you a power boost every 10min the game goes on.

With this in mind, think about the items you build, and aim to build every item with CDR to give you the bonus damage for all Cooldown above 40% (Max).

Thanks for viewing my Thresh Guide! I hope it was helpful.

If you liked this guide or had any questions, leave a comment for me :)

If you didn't like the guide, leave a comment to let me know why and what I may need to change!