>>42951005Hyper Evolutions.
Instead of being a Mega Evolution that forcefully makes a Pokemon stronger, it "corrupts" them into being stronger which ends up fucking up their DNA permanently. This means a Pokemon is constantly in Hyper form until you use an item to force them out of it. It's basically a permanent Mega that you can keep on the team like that as long as you want. You can only have one Hyper Evolution per team.
Pic related can be a Hyper Minior.