I'm writing a story about the Apocalypse suddenly happening out of nowhere, but right before it starts a mysterious HUD (heads-up display) System similar to video games appears to everyone on the planet. The HUD System tells everyone that the Apocalypse is about to begin and it also gives everyone the opportunity to become magically enhanced as a 1st Level D&D 5e character to help them survive the apocalypse. However, if anyone accepts the offer to become magically enhanced, they must suffer some kind of backlash, curse, or determinate.

The reason for the backlash, curse, or determinate is because I don't want everyone in the story walking around with abilities in the apocalypse. I only want around 1% of people who actually accept the offer.

The problem I'm currently having is finding a backlash, curse, or determinate that isn't too severe or horrible to live with, but is also something that only 1% of people all over the world would willing accept. Also, everyone will only have around 10 seconds to accept or decline the offer to become magically enhanced.

Any help is appreciated.