This is not so much a game, but rather a toy/experience sort of thing? Anyway, check it out here: https://martijnfrazer.nl/blues/
It's intended to work on modern web browsers running on desktop / laptop computers. It doesn't really work on mobile devices at the moment.
You can either drag your mouse (moving as you hold the button) across the keys, or just type away and play the piano using your computer's keyboard.
Jamming blues music is one of the staples of playing music together with fellow musicians. Because of its standard format and scale, anyone who knows these things even a little can jump in and join the fun that is improvising music together with other people. Sadly most non-musicians never get to experience this, so I thought I'd try to find a way to simulate it somewhat.
This is not really a game per se, but more an online toy / educational experience sort of thing. The idea is that there's a virtual piano you can play with the keyboard of your computer. The twist is that you can only play notes that are in a blues pentatonic scale, which means that basically all notes will sound alright. To have something to play along with, I've recorded a bunch of backing tracks on guitar which provide a standard 12-bar blues framework. This way you can jam out on the virtual piano along with my guitar playing, so we're effectively jamming together :)
If only I could have a little blue person pop up to encourage me every time I play a keyboard!
I really like your idea of trying to create an accessible way to jam. It would be cool if you could take it a bit further and teach people a little about the theory while they're playing - say by showing which note in the scale is being played, or allowing the user to pick multiple scales.
The blumanoid is particularly cool, especially since you made them using just abunch of divs!