Bastion Bay
Build walls. Place cannons. Hold the bay.
▶ Play Bastion BayFree · plays in your browser on phone, PC or Xbox · no ads in the game
What is Bastion Bay?
Bastion Bay is a castle-defense game played in rounds. Each round has three phases: place cannons inside your walls, fight a timed battle against ships at sea, then rebuild your walls with oddly shaped wall pieces before time runs out. If no castle is fully enclosed when building ends, your bastion falls and the game is over.
Modes
Endless pits you against wave after wave of fleets. Story mode has five chapters and a final battle against the sea beast Murkmaw. Versus puts castles against castles, or castles against fleets, with up to four seats filled by you, a second player on the same keyboard, or computer opponents on easy, normal or hard. Online rooms let friends join with a room code. Maps are generated fresh each game.
How to play
Cannons: place your cannons inside enclosed walls. Enclosing more castles earns you more cannons for the next battle.
Battle: fire at the ships. Caravels take 2 hits and frigates take 5. Cannonballs take time to fly, so aim where a ship is going, not where it is. Shots fired before the timer hits zero still land.
Rebuild: patch your walls with the pieces you're given and rotate them to fit. When the timer runs out you get 3 extra seconds to drop the piece in your hand. Holes don't silence your cannons mid-battle. What counts is what's enclosed when building ends. Red-flag frigates leave burning craters that block building for 2 rounds.
Controls
Desktop: click to place or fire, right-click or R to rotate, drag or the arrow keys to pan, the mouse wheel to zoom, C to recenter, Esc or P for the menu, and M to mute.
Phone (portrait or landscape): tap to place or fire, drag one finger to move the ghost piece and press ✚ to confirm, use two fingers to pan and pinch to zoom, ⟳ to rotate and ◎ to recenter.
Gamepad: Start opens the pause menu, the D-pad chooses and A selects.
Strategy tips
- Build small first. A tight wall around one castle is easier to close in time than an ambitious ring around three.
- Lead every shot. Watch which way a ship is sailing and fire ahead of it, especially at long range.
- Kill frigates before caravels when you can. They take more hits, and the red-flag ones leave craters that cramp your rebuilding.
- Keep cannons away from your outer wall. Cannons left outside your walls after building sit idle.
- Don't panic at the buzzer. The 3-second grace period is often enough to seal one last gap.
The genre it's inspired by
Bastion Bay draws on a 1990 arcade game that mixed two very different ideas: a falling-block puzzle for building castle walls and an action phase for firing cannons at enemy ships. It was ported to many home systems in the early 1990s and is still remembered as an unusual blend of genres. Bastion Bay is our original game in that spirit, with its own maps, ships, story and rules. It isn't affiliated with any earlier castle game.
Developer's notes
Bastion Bay is one of the most-played games in the arcade. We added story mode and the Murkmaw boss to give it a beginning and an end, and we recently rebuilt the phone layout so it plays upright without asking you to turn your phone.
Recent changes
- October 2026: Added story mode with five chapters and the Murkmaw boss.
- Shots fired before the battle timer hits zero now still land.
- Added a phone portrait layout, so you no longer have to rotate your phone.
- Refreshed the arcade thumbnail and graphics.
- Added the ✎ button for suggesting changes.
If you like this, try these free classics
These link to our Free Classics page, where each game points to its official free source.