Maplestory "High Five" Private Showcase

so do you know the formula of defense╭(°A°`)╮

What do you mean? Like how defense is calculated or how damage is mitigated because of defense? Either way the answer is no. There's a difference between those kinds of formulas and formulas that determine how skills grow with level.

Short of something like this happening again:

All of these formulas are taken straight from the executable file. A fully functional, unpacked, and unencrypted exe file was distributed to me legally and free from here.

The only way is to determine them experimentally.