Here’s an idea for a Sonic game:
Sonic gets trapped in a capsule with a mechanism that moves a propeller. This propeller moves him in different directions depending on his speed, and Spin Dashing causes the mechanism to move the capsule up in he spins forward or down if he spins backward. If he gets attacked while the capsule has no Rings, a powerful explosion destroys the capsule and Sonic loses a life.
Sonic gets trapped in a capsule with a mechanism that moves a propeller. This propeller moves him in different directions depending on his speed, and Spin Dashing causes the mechanism to move the capsule up in he spins forward or down if he spins backward. If he gets attacked while the capsule has no Rings, a powerful explosion destroys the capsule and Sonic loses a life.