VICTORY ISN'T SURVIVAL.
VICTORY IS SUPPLY.
Every level you win becomes a working territory in your war economy. Fight well, and that mining colony keeps paying out — bankrolling every mission that follows. Fight poorly, and the next front starts hungry.
Hold the line
Classic tower defense, sharpened. Place turrets, pick upgrade paths, and adapt to alien waves that punish lazy builds.
Turn battlefields into territories
A won level doesn't just unlock the next one — it becomes an outpost that generates campaign income. Your performance sets its output.
Bankroll the next front
Territory income raises your starting currency on future missions. Replay old fronts, defend them better, and squeeze out more supply.
CONTINUE DEFENSE?
Winning is only the beginning. Extract with your income secured — or push into bonus waves and gamble it for a richer territory.
THE ARSENAL & THE SWARM
CRYO TOWER
Freeze the swarm in its tracks. Crowd control for the moments everything goes wrong.
LASER BEAM
Continuous cutting fire that carves through armored brutes before they reach the core.
EMP TOWER
Strip alien shields and stall mechanized units. The support tower that wins boss waves.
TEN FRONTS. ONE WAR.
From orbital platforms to frozen research bases, every region fights differently — and every region you hold pays differently.
CHOOSE YOUR COMMANDER
THE FRONTIER FIGHTS BACK
The biggest update yet. The territories you hold are no longer safe, and the war you wage now follows you from mission to mission.
The Swarm strikes back
Hold four territories and the Swarm starts ambushing the ones behind your front. A hit territory stops paying, and its neighbours run short on supply, until you march back in and reclaim it. Pause new ambushes any time in Settings.
Take back what turned
Veteran commanders may find a territory turned from the inside, its own towers firing for the Swarm. Reclaim it with a convoy of up to six towers marching down the lane.
A war you grow into
Command XP raises a permanent Command Rank and opens a 26-node Doctrine tree across Arsenal, Fortification, Logistics and Command. Reset any branch for free between missions.
Push your luck
Call the next wave early for bonus Credits, but every wave you stack arrives tougher. Bonus waves are a real gamble too: fall during one and that run’s bonus is forfeit.
Know your enemy
A codex of every enemy you meet, with its weaknesses and the towers that counter it, plus a full reference page for every tower and building. Tap any enemy mid-battle to track it.
See where you stand
Earn 28 medals, and with optional Game Center see how your defense compares with other commanders after every territory. Never required: the campaign plays fully offline.
THE SIEGE HAS BEGUN
Frontier Siege is out now for iPhone and iPad — free, with no ads and no in-app purchases. The frontier won't hold itself.
