Swipe/arrows/WASD slide signed ranks. Opposite equal ranks disappear; equal negatives combine into a larger negative. Invert then select an affordable positive2–16; cost is its value in score. Upgrade changes ordinary spawns only, not scheduled negatives/wildcards. Cancel exits selection; R repeats.

Original compact interpretation; scenario rules and goals differ from the inspiration. No copied assets. See source notes and complete QA replay sequences.