Drag to swap and connect same colors (2+) to score. Board resets every 10 seconds — score before the timer runs out or you lose. Every 4 seconds a black line wipes a random row; every 6 seconds a black line wipes a random column and refills it. Every 12 seconds each panel has a 20% chance to change color. Clears spark fireworks; big clusters (5+) explode nearby squares for bonus points.