Ocean Defense is a free online co-op tower defense game rendered in 3D right in your browser. Up to 10 players each take a turret on a seawall and hold back wave after wave of crabs, sea serpents, shell turtles and sea birds — and every fifth wave a boss: the Kraken, the Leviathan, the Crab Titan or the Abyssal Golem. Earn gold, upgrade and evolve your turret, repair stunned teammates and race for the top score. Bots fill empty seats, so a run always starts right away.
Ocean Defense — 3D co-op tower defense
Free · no download · no loginHold the seawall together. Upgrade, evolve, and bring down the Kraken.
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Screenshots
How to play
- Pick a turret: Gatling (fast fire), Cannon (splash and armour piercing) or Frost (slows enemies; chilled enemies take extra damage).
- Aim with the mouse and hold to fire. Between waves, spend gold on damage, fire rate and range, or evolve your turret.
- Watch the seawall health. Repair stunned neighbours and shoot the glowing weak points of bosses together.
- Survive as many waves as you can. When the seawall falls the run ends and your score goes into the ranking.
Controls
- PC: mouse to aim, hold the left button to fire, right-click to zoom, hold E to repair, B for upgrades.
- Mobile: drag to aim, AIM to zoom, FIRE button or auto-fire, REPAIR next to a stunned ally.
- Overview camera between waves; sound, music and graphics quality in Settings.
Features
- 10-seat co-op rooms with bots covering empty seats — play solo or with friends
- Three turret classes with six evolutions, from Twin Gatling to Blizzard
- Four rotating bosses with enrage phases, weak points and cinematic intros
- Daily missions, achievements, turret mastery, boss trophies and a shareable highlight card
- Lag-compensated aiming and procedurally generated 3D models — nothing to download
FAQ
Is Ocean Defense free?
Yes. The game is free; optional rewarded ads give small bonuses like extra gold or an instant revive.
Do I need friends to play?
No. Quick play drops you into a room where bots cover the empty seats; you can still invite friends with a private room code.
Which turret is best?
Gatling for swarms and birds, Cannon for turtles and bosses, Frost to slow everything and raise your team’s damage. Mixed teams win.
Does it run on my phone?
Yes. The 3D renderer scales its quality automatically; use the Graphics setting on older phones.
How many waves can I survive?
Bosses come every 5 waves and get tougher. Reaching wave 20 earns the “Legend of the wall” achievement.
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