Boulder Dash, explained
This is a free, modern browser game in the spirit of the 1984 classic Boulder Dash: you dig through underground caves, collect enough diamonds to open the exit and get out before the time runs out, without being crushed by a falling rock or caught in an explosion. The caves, the graphics and the sound are new, but the rules of the cave are the ones that made the original famous.
Where does Boulder Dash come from?
Boulder Dash was created by Peter Liepa and Chris Gray and released by First Star Software in 1984 for the Atari 8-bit computers and the Commodore 64. It mixed real-time action with puzzles: every cave is full of rocks and diamonds that obey gravity, so each step you dig changes what falls next. The game was ported to dozens of systems and inspired countless remakes. This page is an independent tribute and is not affiliated with the rights holders.
How does the gravity work?
The cave updates several times a second, from the top row down. A rock or diamond with empty space below it starts to fall. When it lands on another rock, a diamond or a brick wall, it rolls off to the left or right if there is room. A falling rock is deadly, but a rock that is already resting on your head is not: you can walk under resting rocks, as long as you do not dig away what holds them up while you stand below. Diamonds behave exactly like rocks, so they can crush you too.
Can I push rocks?
Yes, sideways only, and only if the space behind the rock is empty. Keep pushing for a moment and the rock rolls one step. You cannot push rocks up or down, and you cannot push diamonds; you collect those. Hold Shift or Space (or the GRAB button on a phone) and press a direction to dig dirt or grab a diamond next to you without stepping into its place. That is the safe way to take a diamond from under a rock.
Fireflies, butterflies, amoeba and magic walls
Fireflies are the spinning orange squares. They follow the walls of their tunnel, always trying to turn left. If one touches you, it explodes and takes you with it. A rock dropped on a firefly makes it explode into empty space, which can also open a way through brick walls. Butterflies follow the walls the other way round, and when a rock lands on one it explodes into nine diamonds; in some caves that is the only way to collect enough. The green amoeba grows slowly into dirt and empty space and speeds up after a while. If it can no longer grow because it is boxed in, the whole amoeba turns into diamonds; if it gets too big, it turns into rocks. A magic wall wakes up when the first rock falls on it. For a limited time, rocks that fall through come out as diamonds, and diamonds come out as rocks.
The twelve caves
The campaign goes from First Steps and Loose Rocks, where you learn how rocks fall and roll, through Firefly Tunnels, Butterfly Garden, Amoeba Grove and Magic Wall, each built around one idea, to the maze, the avalanche, a short Rush Hour, the big Deep Mine, Twin Caverns and a Grand Finale that combines everything. You start with three lives. Clearing a cave unlocks the next, and you can replay any unlocked cave for a better score or three stars.
Random and daily caves
Random cave builds a fresh cave every time, with its own mix of rocks, diamonds, enemies and sometimes an amoeba. The daily cave is the same for everyone on the same day, so you can compare scores with friends. Your best daily score is saved for that day.
Tips for the later caves
- Look before you dig. Removing one tile of dirt can start an avalanche that blocks your only way out.
- Dig towards a rock from the side, not from below, and step away straight after.
- Use grab to take diamonds from under rocks without standing in the danger zone.
- Lure fireflies and butterflies under rocks: open their chamber, wait until one passes below a rock, then dig the dirt that holds the rock.
- When the exit opens, an arrow at the edge of the screen shows the way. Do not get greedy with seconds left.
Phone, tablet and gamepad
On a touch screen you can drag anywhere on the cave like a joystick: keep your finger down and the miner keeps walking. The on-screen pad with a GRAB button appears automatically on touch devices and can be turned on or off in the settings. Gamepads work out of the box. The game pauses itself when you switch tabs, and a relaxed speed setting slows the whole cave down.
Saving and privacy
Your unlocked caves, stars, best scores, high score and settings are saved in your browser's local storage. Nothing is sent anywhere. The level you reached in the previous version of this game is carried over.
More free tools