Hollow Moon is a new retro FPS that you play right in your browser: a fast first-person shooter set on a mining station on the far side of the Moon. You are Juno Marek, the night technician of the deep drill, and the drill has just broken into a sealed vault under the crater. What was shut inside is climbing the shaft, and the only way out is down.
Key Takeaways
- Hollow Moon is a retro first-person shooter with four levels, five weapons, five kinds of creatures and a boss, the Warden, who guards the vault under the crater.
- The big idea is decompression. Shoot out a window and the air rushes into space, dragging light creatures with it. Each one lost that way is a vented kill worth 50 percent more points.
- Venting has a price: the room becomes vacuum, your suit starts to use its own oxygen, and airlock doors stay shut until the pressure matches again.
- Your weapons are mining tools: a wrench, a rivet gun, a mining scattergun, a plasma cutter and a charge thrower.
- An objective line, a compass arrow and a map keep you on course. There are three difficulties, and the game plays on desktop and on phones held sideways in English, Spanish and German.
A retro FPS on the far side of the Moon
Selene-7 mines helium on the far side of the Moon, out of sight of Earth. At 03:12, in the middle of the night shift, the deep drill went through into open space under the rock: a vault with carved walls, older than the crater above it. The Moon is hollow, and what was shut inside it is awake. By the time you take over, the crew are gone and the comms are dead. Juno takes a rivet gun and goes down to close the vault.
Hollow Moon plays the way the first-person shooters of the early nineties did. You run fast, strafe around corners, hunt for coloured keycards, ride a lift and look for secret rooms. You turn left and right only. There is no looking up or down, and a shot finds a creature above or below the crosshair by itself, so the pace stays high on a keyboard and the game works on a touch screen too.
The story is told in the same old way: a few panels at the start, a title card for every level, one line between levels and green terminals where the crew left their last logs. Read them. Some are warnings, some tell you where a keycard is kept, and one tells you how to deal with the thing that guards the vault.
It looks the part as well: chunky pixels, deep shadows and things that glow in the dark. You go from the station's decks and refinery out under a black sky full of stars, and then down into dark carved stone marked with gold glyphs. The survey log says the glyphs repeat one shape: a door, closed.
Decompression: shoot out a window and let the vacuum work
Decompression is what makes this retro shooter its own. Selene-7 is a thin shell of air in a place that has none, and you can open that shell whenever you like.
Windows with a yellow frame break. Shoot one out and the room's air rushes out through the breach. Deep in the vault, emergency valves do the same job without any glass. For a few seconds a gale drags light creatures and loose items to the hole and blows them into space. Every creature lost that way counts as a vented kill and scores half again as much as one you shot. Juno gets pulled too, but she holds on.
Then the gale stops and the bill arrives:
- The room is vacuum. Your suit switches to its own oxygen, and the O2 bar starts to drop.
- Airlock doors lock. A door will not open between air and vacuum until the pressure on the two sides matches, so a vented room can close the way you meant to go.
- Loose items are gone. Ammo and med kits lying on the floor go out with the air. Keycards and weapons stay where they are.
To undo it, find the room's seal switch, the blue panel with bars. It drops a shutter over the hole and lets the air come back. So venting is always a choice with a cost. A room packed with skitters is a good reason to break the glass. A single husk between you and the med kit you need is not.
Oxygen, airlocks and low gravity on the surface
Your suit holds around half a minute of oxygen. It drains in vacuum, refills by itself in any room with air, and an oxygen canister fills it at once. When it reaches zero you start losing health quickly. If the supply runs low, the objective line at the top of the visor changes to "Low oxygen: get to air" and the arrow turns to the nearest place you can breathe.
Airlock chambers let you cross between air and vacuum without venting anything. Use the door, wait while the chamber cycles to the pressure of the other side, and walk through.
On the open surface there is no air at all, and gravity is low. Jumps go long and slow, far enough to clear crevasses you would never clear indoors. Fall into one and the level starts again. The surface level is a string of domes with airless ground between them, so plan each walk before you leave the airlock and keep moving once you are out.
Four FPS levels from the crew decks to the vault
The run has four levels, and each one adds something to the fight.
- Habitat Ring is the crew decks. It teaches doors, keycards and your first window, and the mining scattergun is waiting here. Husks and skitters are the first things you meet.
- Helium Works is the refinery: a lift, catwalks over the refinery hall and pressurised helium tanks that burst when shot. The plasma cutter is somewhere in the hall, and spitters and lanterns join in.
- Farside Traverse is the open surface, with no air, low gravity and oxygen to manage between the domes. The charge thrower is out here, and so are the rams.
- The Hollow drops down the drill shaft into the carved vault, where the Warden waits.
Every level has two secret rooms and three terminals with short logs from the crew. When you reach the exit pad you get a summary: kills, vented kills, secrets, your time against the level par, accuracy and deaths.
Mining tools for weapons, and what came out of the vault
Nobody on Selene-7 was armed, so Juno fights with what a drill crew keeps around.
- Wrench. Always there, never runs out, and only useful up close.
- Rivet gun. Your starting weapon, precise at any range.
- Mining scattergun. Hits hard up close.
- Plasma cutter. Fires fast over a short reach.
- Charge thrower. Lobs seismic charges that explode. Keep your distance from your own blast.
Ammo, med kits, stim shots and suit plates are scattered through the levels. Keys 1 to 5 pick a weapon, and Q or the mouse wheel takes the next one.
The creatures each fight in their own way. Husks walk you down. Skitters rush in packs. Spitters sit back and lob globs at you. Lanterns float and burn from a distance. Rams charge in a straight line across open ground, take much less damage from the front than from behind, and are too heavy for the gale to carry off. Step aside and shoot them as they pass.
Then there is the Warden. It guards the vault at the end of the last level, tall, gold and stone, with a swarm of glowing shards circling it as a shield. That shield turns most of your damage aside. Its hall has three emergency valves. Open them one at a time: each rush of escaping air tears away a third of the shield, and while the hall is without air the Warden cannot fire. That is your moment to hit it hard.
Tips and controls for your first run
- Follow the visor. The line at the top names your next step and the arrow points to it. Tab opens the map, where an orange ring marks the same spot.
- Read the doors. A green light means a door will open. A door framed in a card colour needs the amber, cyan or magenta keycard.
- Look before you break the glass. Pick up what is lying around first, and check where the seal switch is.
- Mind the tanks. A helium tank that bursts hurts everything near it, and that includes you.
- Start on Cadet if shooters are new to you. There are fewer creatures and they hit softer.
On desktop, WASD moves and strafes, the arrow keys move and turn, and the mouse turns once you click into the game (Esc lets go of it). The left mouse button, Ctrl, J or F fires, E or Enter uses doors, switches and terminals, Space jumps and P pauses. A gamepad works too. On a phone or tablet held sideways, a stick on the left moves, a drag on the right half of the screen turns, and FIRE, USE, JUMP and WPN do the rest.
Score, difficulty and the leaderboard
Three difficulties change how many creatures you meet and how hard they hit. Cadet multiplies your score by 0.6, Driller is the station as it is, and Nightwatch sends everything at you and multiplies the score by 1.5.
Each finished level scores points for every kill by creature kind, half again for vented kills, 500 for each secret room, 10 for every second under the level par and up to 600 for accuracy. Sealing the vault adds 5,000. If you die, the level starts again with what you carried into it and full health, but the clock keeps running and each death takes 500 points off.
A full run from the first level goes on the shared leaderboard. You can also continue from a level you have already reached, but a continued run is not ranked. Three achievements are waiting: Out the Airlock for your first vented creature, Vault Sealed for beating the Warden and Nightwatch for doing it on the hardest difficulty.
Frequently asked questions
How do I play Hollow Moon?
Open the game page and press Play. Move with WASD, turn with the mouse or the arrow keys, fire with the left mouse button and use doors and switches with E. Get from the start of each level to its exit pad, and in the last level beat the Warden to seal the vault.
What is decompression in Hollow Moon?
Shooting out a window opens the room to space, and the emergency valves in the Warden's hall do the same. For a few seconds the air rushes out and pulls light creatures through the breach, and each of them counts as a vented kill worth 50 percent more. After that the room is vacuum and your suit runs on its own oxygen until you reach air, a canister or a seal switch.
Can I play Hollow Moon on my phone?
Yes. Hold the phone or tablet sideways. A stick on the left moves Juno, a drag on the right half of the screen turns her, and four buttons fire, use, jump and change weapons.
How do I beat the Warden?
Strip its shield with air, not with ammo. The Warden's hall has three emergency valves, and each one you open tears away a third of the shield. While the hall is without air the Warden cannot fire, so that is the time to do damage.
What happens when I die?
The level starts again with the weapons and ammo you carried into it and full health. The level clock keeps running and each death takes 500 points off the level score.
What languages is the game available in?
English, Spanish and German, like the rest of PixelDen.
Play Hollow Moon now
Hollow Moon is a full retro FPS you can start in seconds: four levels of keycards, airlocks and secret rooms, tools for weapons, and a station where one cracked window changes the whole fight. Break the first one in the observation lounge and watch what the vacuum does. Play Hollow Moon in your browser, and when you want more, try the first-person corridors of Dungeon Cast, build a ship from wreckage in the space shooter Scrapwing, or browse the full game catalog.