Enemies move along a path leading to your base. Construct towers, foundations, and supporting infrastructure to defeat them. each one that leaks costs a life, and losing them all ends the run.

Gold is optained by destroying enemies, bosses and surviving waves. You can queue placements ahead of your gold, they start construction once you can afford.

• Gunner: cheap, fast all-rounder.
• Sniper: long range, heavy single shots. Great for tough targets and bosses.
• Trap: sits on the path to slow and stun.
• Breacher: short-range shotgun that shreds packed groups.

Tap towers to upgrade or set its targeting mode. Group towers on a Foundation and fortify it with a Fence or Wall to blunt drone damage.

• Shielded: ringed by 4 shield sections with gaps between - AP gunners and snipers chip a section down, then shoot through the gap or the hole they made.
• Runners: fast and fragile, won't dodge traps.
• Drone operators: launch drones at your towers - Anti Drone specialists down them.
• Bosses: every tenth wave, and waves toughen the longer you last.

Enemies march along the path toward your base. Build towers beside the path to destroy them before they reach the end. Each enemy that leaks through costs you a life. Lose them all and the run is over.

You earn gold for every kill. Tap the build menu, pick a tower, then tap an empty tile next to the path to place it. Towers you can't afford are dimmed. You can queue placements ahead of your gold, and they build automatically as you can pay for them.

• Gunner: cheap, fast, all-rounder. Upgrades into the Autocannon line (High Explosive that bursts on hit or Armour Piercing that pops shields).
• Sniper: long range, heavy single-shot damage. Great for tough targets and bosses.
• Trap: deploys on the path to slow and stun enemies passing over it.
• Breacher: short-range shotgun that shreds tightly packed groups.

Tap a placed tower to open its menu. Spend gold to upgrade it down a spec tree that changes how it fights, and set its targeting mode (first, closest, strongest, or a fixed lock). Group compatible towers on a Foundation to manage them as one, then fortify it with a Fence or Wall so drones do less damage to every tower on it.

• Shielded enemies wear a ring of 4 shield sections with gaps between them; each section takes a quarter of the shield's health. Armour Piercing gunners and snipers wear a section down, and once it (or a gap) is open, rounds pass through to the body.
• Runners are fast and fragile, and won't dodge traps.
• Drone operators appear later and launch drones that attack your towers directly. Anti Drone specialists shoot them down.
• Bosses arrive every tenth wave, rotating through Silverfish, Bulwark, Phantom, and the Command Station. Waves become tougher the longer you last.