Frontline Defender.

Frontline Defender: automatic base defense

Collect coins to build and upgrade your defenses automatically. Pilot a tank, mark fighter airstrikes and call allied paratroopers in a free-roaming 2D battle.

Roam a 2,600 × 1,900 battlefield with a following camera. Protect a 500-health HQ, survive six waves and destroy three orange generators. The last wave includes a commander. There is no forced scrolling. Start with 100 health and 150 field coins; the default Auto base mode starts investing those field coins immediately.

A more detailed military battlefield

Your soldier and allies wear helmets, vests, packs and rifles; enemy uniforms and armbands keep teams distinct. The tank has animated tracks, armor, an independently aimed turret and cannon recoil. The helicopter has a cockpit and rotor, the fighter has paneling and an exhaust, and the transport deploys soldiers under parachutes. Defenses add sandbags, machine guns and reinforced level-two concrete.

The terrain adds grass, roads, shell craters, ruins, trenches, ammunition crates, barrels and burnt-out vehicles. Explosion fire and debris are visual effects and add no damage. Ruins, crates, trenches and other scenery are decorative; only built walls block movement. The map, six waves, costs and combat rules remain the same.

Computer and mobile controls

• WASD or arrows move; mouse aims and holding click fires. Space shoots toward the nearest enemy. On mobile use the left movement stick and the right aiming/firing stick.
• F or Target fighter arms targeting without charging coins. Then click or tap a point on the battlefield to pay 120 and send a fighter. Press F again to cancel. A bomb hits after about 1.2 seconds.
• R calls three allied paratroopers at your position. H calls a helicopter near HQ. Buy a tank near HQ, approach it and press V to enter. V exits to the right when there is room.
• E completes or upgrades a nearby building immediately if you can pay its remaining cost. The buttons below the game provide the same purchases. Escape or Pause pauses the mission.

Coins build your walls and towers

Auto base invests progressively in fixed pads around HQ even while you explore. It builds empty turrets first, then walls and the control post, before upgrading them to level 2. A gold stream and investment bar show what is being funded. Part-paid construction stays on its pad until completed; walking away does not lose it. A pad is skipped if the player stands on it.

Proximity mode only invests within 125 units of a pad. Standing near the marked H helipad can also fund a helicopter when no nearby building is eligible. Manual stops automatic spending, letting you save for a tank, airstrikes or infantry. Manual purchases require proximity to buildings or HQ where indicated. Auto base does not automatically purchase tanks, fighter strikes or infantry.

Patrols, helicopter, tank and repairs are purchased within 230 units of HQ. Fighter strikes and paratroopers work anywhere. Destroyed defenses lose their level and can be rebuilt; Repair only heals surviving structures. Allies follow and fire automatically and currently have no independent health system.

Optional boosts before a mission

These use the portal’s Arcade Coins, unlike field construction. A helicopter start costs 120 and provides 25 seconds of support. An HQ shield costs 80 and absorbs the first 100 damage. Speed boots cost 60 and increase on-foot speed by 15% for the mission; tank speed is unchanged. Buy an item, select its checkbox and start: one selected unit is consumed. Buying alone does not consume it. Buying a boost also selects it for the next mission; uncheck it to save it. All missions remain free without boosts.

Loot, portal rewards and saving

Normal enemies drop 12 field coins; the commander drops 80. Generators award 45 field coins directly. Collected loot also gives 1 Arcade Coin; starting a wave gives 2, each destroyed generator 8 and victory 25, sharing the 150-coin session bonus limit. Final results save automatically and use the usual separate 5–50 coin reward after ten active seconds.

Field cash, buildings, upgrades and vehicles belong to this mission and reset on a new run. Portal coins and unused boost inventory stay in this browser. Closing an unfinished mission does not save its battlefield. The leaderboard remains personal and local.

How do I save for a tank or fighter?

Select Manual construction to stop automatic investment. Gather loot, then spend 250 at HQ for a tank or mark a fighter strike for 120. Re-enable automatic construction when you want to finance defenses again.