The Poke Virus

The Poke Virus is a Virus that makes 1 Pokemon (or you're whole team) stronger. This only happens in the video games from Ruby and Sapphire to now.

How it happens
Sometimes, when you don't know it, you capture a Pokemon with a Virus. The only way you can see it is when you look at your Pokemon's stats.

How to remove it
It removes it by itself, but remember, it makes you're team stronger!