For as of now, theres only one ending, however, if you mean the last four glitch levels, they're all unlockable, but they're all hidden !! hope this helps
I got the first two glitch levels! Any hints on how to obtain the rest of them?
Sure! and for anyone else who plays in the future, i'll leave the hints:
Check the Data folder for a hint!
Click the hidden button!
Have you tried bending backwards?
Unlocked when you find all 3.
Pretty sweet!
How do I attack the King during his boss battle, though?
When you collect basketballs during the fight, you can jump at their head and damage them