This is an ADC Thresh guide and you may know that the passive on his Q will do 200% of your ad as magic damage. This cannot crit so the phantom dancer is just to have extra pushing, if heavily fed feel free to replace with a sword of occult.

Early game you want to try to keep up last hits and pick pocket/poke the other adc. This may be hard if your against a person who can poke easy. If against someone like this pull them to you and try to flay them back so your support can help you secure the kill. Great supports with Thresh ADC are blitz, alistar, and shen so when you pull them they dont get away. You want to have good communication with your support and make sure they know when your going in. Maybe have a target system using smart ping. The barrier is mostly there incase you get dived. If you are getting turret dived barrier to block the shot that wouldve killed you, pull, lantern, basic attack, and flay. Unless they are full hp this should kill them. But in the event you are running if your 200 hp and there only 400 or so then flay, lantern, and basic attack.

By now people have started roaming more often and theres a turret or two down. You should on your final part of infinity edge or farther. At this point if you are not fed then try to pull and flay people away from you trying to let your team do damage whilst the person is stunned and finish it with a basic attack. If you are fed then walk around wait for your RED passive to be up and pull to them flay and basic attack until there dead. If your fed but your team was feeding then I suggest you do the same as when you aren't but let your team get the kill. When pushing you usually want to attack tower until your RED passive is up then attack 1 minion and usually insta-kill it. When in team fights feel free to grab anyone except for the tank or bruiser and beat down on them with your OP passive or come in assassin and q,q,e,r,w then basic attack (Usually wanting to do on the adc but if you heavily denied there adc farm then use on there mid or apc) make sure your team knows your going to do this.

It is easy to steal baron if you have your jungler with you. You just have your jungler run in and steal then you throw your lantern and bring them back. With a darius or blitz on your team you may get a kill out of this being able to take an enemy over the wall. If needing to secure baron then grab the intruder and hold or kill until baron is dead. Do not let your whole team focus them seeing as someone else from there team can still steal. When pushing you can easily take someone from there team away from the tower and have kill them. When escaping from team fights or initiating them use your ult because it slows majorly with high damage.

Having the extra gold from pickpocket and easy farming you will most likely have the most money on the team. This was my first guide so please rate honestly and if there are problems or changes you think would be well comment.