Witch's Brew
It's pretty odd that this game even exists for the stock MD. Success, a game company that never made anything for the console prior to this (though I think some devs come from Compile), decides to turn Cotton into a Space Harrier-like shooter, make it one of the most technically impressive efforts for the system, then release a limited amount of copies exclusively for the Japanese market as late as mid-1994. Well I'm glad they did, because they certainly succeeded in making Panorama Cotton an amazing game with some unusual depth for the genre - for example you get various branching paths and RPG elements years before Panzer Dragoon Zwei here, every level has a new set of enemies, several sub sections with detailed and trippy environments, and there's an impressive boss at the end of each one. PC is something of a swan song for the 2D-based rail shooter.
Now if someone would port this to the MCD for super smooth scaling...