You can have any superpower, but the first person to reply chooses a side effect

Each day you don't poop, you lay an egg that hatches into a random monster. The egg is indestructible.

You have to post about it online and keep the community updated on your progress, becoming the first widespread Lemmy meme

But when you eventually poop your in the middle of human a human centipede

You already can -- immodium

This is very healthy and has no possible downsides.

You have tk participate in a mysterious and most likely kinky event.