What is "on tilt"?

Pissed off/frustrated, possibly performing poorly because of it, possibly more likely to quit, rage, or troll.

Being on tilt means that one's performance begins to worsen as he/she loses or starts to lose a game.

Some one has gone over the edge, and are not coming back. Essentially it means they've lost all ability to have logic or reason and will continue or start to play bad because of comments or teammates.

There's a lot of specifics to different forms of tilt, but basically, it's a mental state that causes your decision making in the game to worsen, and thus causes you to perform even more poorly. It often diminishes or annihilates all map awareness, makes people play to extremes (super passive or super aggressive), can cause people to just troll/afk/ragequit games.

Tilt is extremely common when you have a string of bad games, have an excessively poor performance in one game, get camped super hard by the jungler and/or other lanes, get crushed in 1v1s, throw a huge advantage, and many other things, but those tend to be the most common causes.

It's the mindset that if you ever find yourself in it you need to stop playing for a little while as it just compounds upon itself over and over.

When you lose a bunch of games and you get demoralizes and lose concentration which affects your decision making and makes you lose even more games.

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