I'm sick of explaining to people that Master Yi has more counterplay than "Just CC him"

There are 3 broad ways to counter Master Yi.

1. Getting ahead early. Master Yi does not have a "weak" early game in the way that you might think. He can overpower most enemies in a head-on 1v1. He does, however, have difficulty making impact on the early game. He does not have CC. He does not have the kind of mobility that can hop over walls, or that he can use to escape from trouble. At level 6, Highlander is slow. Altogether, this means that almost every other jungler is better equipped to gank, counterjungle, and contest objectives in the early game. Assuming players are of equal skill, Master Yi and his team should be behind until Master Yi has levels and items.

2. Disengaging. Master Yi wants to fight you. He is a stat check, and one of the strongest in the game. So to beat him, the trick is to pull out the rug from under his feet. Use your spells at strange timings so that he won't know when to Alpha Strike and dodge them. Flash into an unfavorable position (for him) when he Alpha Strikes you. Use a stopwatch or hourglass when he's on you - this means he will get a kill (and a reset) much later than he planned to, and he'll be exposed while he's waiting around for Alpha Strike to come off cooldown. If all else fails, you can run away! Seriously, he's not that fast. You don't need to run faster than him, just fast enough that he has trouble auto attacking you. He can be forced to use Alpha Strike to gapclose, and if he does that, he becomes vulnerable. If you can survive for just 7 seconds, then his Highlander runs out and he almost completely stops being a threat. If you look at the majority of champions in the game, they have ways to disengage from Yi:

• Aatrox - revive passive makes him untargetable for a few seconds.

• Ahri - dash away, Yi can't keep up.

• Akali - Yi can't attack her in shroud.

• Anivia - Yi has to kill her twice before he gets a reset.

• Annie - stun wastes a lot of Yi's time.

• Amumu - two hard CCs.

• Alistar - Headbutt actually wastes a lot of time, it can create a huge gap between Yi and the champion he's trying to kill.

3. Grouping. Master Yi is not an invincible one-man army (usually). His damage is mostly single-target, Alpha Strike only does approximately one basic attack of damage and does not apply on-hit effects. He's limited in how often he can Alpha Strike, if you have just two CC spells on the team then you can stagger them and he won't be able to dodge both. He has almost no opportunity to protect himself with Meditate because someone will interrupt him. Master Yi just can't survive for long at all, standing in the middle of 4-5 enemies.