I am making a short hack I'd say 6 exit's, at this stage I have called it: super scroll world. the plot, its an average story, peach kidnapped, you must save her but with a slight twist. You encounter a magikoopa who casts a spell on you and makes you feel funny not realising you are possesed.
the game is dual-narrative in a way. As on one level you enter a pipe and you end up on another level and go back to the first level.
I'm gonna step out on a limb here and guess that this wasn't tested to be beatable without savestates.
Level design is just spam one sprite/block for the entire level in a fast autoscroller, then you either attempt to dodge or jump on every sprite/block. 1st level urchins 2nd level noteblocks etc.
Since the level's are fast autoscrollers you basically have to know whats coming ahead and know exactly how long to hold your jumps before you even see the obstacle. Even knowing whats ahead doesn't help too much.
I quit on the castle that was a vertical drop level falling through death spikes with multiple paths that killed you.
If this hack was made to be played with savestates then kaizo:hard was the category you are looking for, unfortunately the hack probably wont be accepted there unless you improve the level design.