After a 30-second build phase, send creeps to the next player clockwise: tier 1 Q W E R, tier 2 A S D F (unlocks 5:00), tier 3 Z X C V (unlocks 10:00). Shift = ×5. Each one you buy adds to your income, which pays out every 10 seconds.
Click one of your towers, then G to upgrade it or Delete to sell it.
Creeps get tougher over time. The last player with lives left wins.
Click any board or player to look at it · Space = your board · right-drag to pan · scroll to zoom