Mercury — free browser game

A flat metal tray holds several mercury droplets scattered across it. Tilt the tray to slide the droplets around; when two touch, they merge instantly into one bigger sphere (total area is conserved, momentum transfers). Hold arrow keys or WASD on a keyboard — the direction you press is the direction of gravity. Release to let the tray return to flat. On mobile, touch and drag inside the scene; distance from center sets tilt strength. The tray has dark sinkholes that drain mercury on contact, and a droplet that shrinks too far gets silently absorbed. The tray edge is a wall and droplets bounce off it. The round ends when only one droplet remains, opening the next level — droplet count and sinkhole count grow each level, and your starting mass is added to your score. Score = preserved mass percentage × level bonus. If all droplets vanish, the game ends. Strategy: use small nudges instead of full-tilt slams; rock the tray corner-to-corner to keep moving past sinkholes; merge two medium droplets first so the resulting giant can chase the rest.