what are your favourite hidden gems of the console?

so I'm a youtuber/streamer and had an idea for a stream/video

I work my way through each console, finding people hidden gems, not your typical top 10 of the generation, play them for 20 minutes and tier list them

I'm a huge retro fan (I'm old) and am really looking forward to trying this out

I'm starting with megadrive/genesis and making my way through the years form there

so what hidden gems have you got for me?