Level 2 All-in:

Any bot lane can benefit greatly from this. Being level 2 against level 1 practically ensures a kill or enemy Flash. The third melee minion on the second wave is where you get to level 2 bot lane (presuming you received all the exp from the first wave). To achieve the level advantage, the strategy is to assist your adc in killing these three melee minions. Thresh should begin approaching the opposing laners when the third melee minion has roughly 50% health left in order to flay or Flash + flay into a death sentence. This will lead to a kill or, at least the opponent’s wasting summoner spells.

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Warding:

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Teamfighting:

Throughout the entire game, team fighting as support typically stays the same. You always have to choose between peeling your carry/carries, starting fights, or both in some uncommon circumstances. As Thresh, your role is more likely to include peeling than engaging, don’t get confused. You are effectively carrying out your duties as long as you withdraw after the initial Death Sentence and avoid front lining.