You're flying through a four-dimensional foam, seeing the 3D slice of it you're in. Fly through its membranes freely. Don't touch its edges, the lines where three cells meet, called Plateau borders in real foam, or the walls of the solid cells.
Every turn turns you through w too: roll and your nose tips into w (the gauge on the right shows how far), so flying forward drives you through the fourth dimension, and the foam around you changes as you go. Pick the crystal you start in. It melts, then cells clot solid, then the foam presses smaller. How far can you get?
Mouse (click to grab it) or arrows steer · A D or Q E roll · on a phone, the stick steers and ⟲ ⟳ roll.
the foam, phase by phase · how it works · foam⁴, the toy · the arcade