Keep Prime Numbers

Keep Prime Numbers is a browser puzzle about separating prime and composite numbers through block removal. The goal is direct: remove all the blocks needed to make composite numbers go out while keeping the prime numbers in place. Its controls are equally simple, with players clicking or tapping unused blocks to drop the composite numbers. That small input gives each move weight, because removing support changes what can fall and what remains protected. The clean setup keeps attention on arithmetic recognition and spatial planning. Instead of clearing pieces blindly, players need to identify which numbers should leave and judge how each removed block affects the rest of the arrangement. A risky early removal can trap a prime number or disturb a position that looked safe, so the obvious move is not always the best one. Strong play comes from reading the layout before acting. Patience, pattern recognition, and care with prime placement matter more than rushing through clicks or taps.