Position towers along the path to defend against waves of enemies.

Defeated enemies earn you money for new towers and upgrades.

Finish every wave to win. Stop every enemy for three stars. Later challenge maps restrict towers; their briefings explain the available tools.

Gold-rimmed power pads give towers 25% more range, including support aura radius. The bonus stays through upgrades and combines with support buffs.

Relay missions introduce square gold pads marked RELAY. An attack tower on a relay fires 35% faster when a different tower type is within two tiles (96 pixels, including across the road). The partner can stand on ordinary ground. Matching tower types do not link, and extra partners do not stack. Support towers can activate relays and add their usual aura. Gold lines and LINK / IDLE labels show the connection; selling a partner breaks it.

Hover Start Wave to preview the next enemies. Use 1–9 to choose or switch towers; press the same key again to cancel. Use U to upgrade, Q to sell, and Space to start a wave.