Built an endless Hill Climb Racing-style AR Lens entirely through prompting in Lens Studio's Developer Mode — no manual scripting, just iterative prompt-and-fix cycles. Real 2D physics on the vehicle (not scripted movement), procedurally generated hill terrain, coin collection, a fuel system, and a balance mechanic where gas and brake fight gravity to keep you from flipping. Every system — terrain, physics tuning, UI, scoring — got built, tested, screen-recorded, and re-prompted until it felt right.