Small, fun one
What I learned from this is that the replaceAll function on string is not present on older version of NodeJS

That's an interesting way to look at it : you are checking whether on average the hero would have enough bullets to kill each dragon (need at least 2 bullets to kill a dragon)

You could save them to GitHub in a private repository.
That way you have access to them, and no one sees it.

But on GitHub I think you can only have one private repository for free.
On GitLab you can have multiple ones ( that's what I use to store my code for other solutions).

I don't see how doing it that way would be cheating.
Storing it locally isn't great when working on multiple devices (like a laptop and desktop).