Tip: You can use Lunar Magic's Overworld Layer 3 Editing system to edit or create your own layer 3 images (castle bricks, fish, rocks) and apply unique effects per level via the Layer 3 Bypass in the main editor.
This is a hack I literally made in 24 Hours for C3. It has 4 short kaizo levels that use basic mechanics.
It's vanilla with exception of some patches.
Moved onto new rom and made things faster!
-OW speed is faster
-Replaced old glitchy goal patch with new, much quicker version.
-Also tried to fix cheese with yoshi and thwomp weave, but I suck at kaizo, so I can't tell if it's still here.
Tweaked level design a bit to fix a few situations that you can cheese as well as to make hack overall slightly easier (for example very first shell jump, many people seem to have struggles with it).