Side-scroll run
The camera cuts to a flat side view and the world loses an axis. One stick, one jump, twenty-five seconds.
The camera cuts to a true orthographic side view. Depth is gone. Your input collapses to one axis plus a jump, the Z axis gets locked out of the physics entirely, and obstacles start scrolling at you for about twenty-five seconds.
This is the one that proves the point. Bowling changed the framing; this changes the shape of the game — the number of dimensions you’re allowed to move in — using the same marble, the same solver, and one swapped-out physics profile.
If that abstraction can survive losing an axis, it can survive anything.