if I had to recommend one game that I think definitely passed under people's radars, it'd be Mad Rat Dead. and it's almost criminal that it'd come to this with how good the game is!
such an interesting take on rhythm games and platformers, the controls do take some time to get used, and it certainly won't be everyone's cup of tea (I remember some parts being REALLY hard) but man is it cool!!!!
the game just oozes with style through it's cutesy/gorey artstyle, beautiful backgrounds, a soundtrack that KICKS ASS and a charming story that definitely caught me off-guard with how invested in it I ended being and how good it was overall.
definitely what I'd call a hidden gem!