Counterplay
Patch 26.15SketchCounter Master Yi
The opponents who give Master Yi trouble, and how to handle each one.
Where these numbers come from
They are pulled from the mode's own files for patch 26.15, the one currently live. The source is community-run rather than an official Riot API, and the game shifts with community votes, so a gap with your own game is always possible.
Rammus is your worst nightmare and he knows it. His spiked shell reflects your own attacks, and his taunt forces you to hit him at the worst moment, control active, while the rest of his team piles on. Never target him in a teamfight, ever. Wait until he has wasted his taunt on an ally, then go around him to reach the backline. If the enemy team has a Rammus, your patience is no longer a virtue, it's a requirement.
Jax turns your own kit against you: when he raises his lantern, he dodges your basic attacks and stuns you right after. Never jump on him while he has it up, you hand over the stun for free. In a duel, let him trigger it first or play it three-on-one once his abilities are spent. In a teamfight, ignore him and find a target that can't punish you: Jax lives on the duel, deny him one.
Nasus has just one button to save for you, and it's enough: his wither collapses your attack speed and movement speed, exactly what makes you dangerous. Under it, you kill nothing and can't run. Keep Alpha Strike to break contact instead of using it to engage, and don't dive while his wither is up. Target him last, once he's already spent it on an ally.