Update:

I'm currently working on updating Tomb Gator from a demo to a polished game

So far I've added more levels

Started colorizing it for Gameboy color

Tweaked some graphics

and I added secret bonus rooms!

I plan to have 21 levels in total not including the bonus rooms. I also want to figure out how to save a high score.

Any other suggestions are welcome. I want to keep it simple as this is an arcade style game. Nothing fancy, just as authentically retro as possible.