Thank you for you awesome feedback!
I didn't though about small custom keyboards... I can add WASD movement and mouse to shoot and charge, the thing I didn't do it like that is mainly cuz clicking all over the browser would make players missclick outside a lot and lose focus from the game.
I will add extra (J,K,L,I) movement keys on next update for small keyboards like yours :)
There is a secret key (1 numeric key on your keyboard) to automatically set the boss hp to 1 or instantly kill it and move on the next boss, if you wanna see all the bosses that's a good way to do it.
The secret key will be removed later on for the stream phase <^w^>