Iron Lung

About Iron Lung

Iron Lung is a short horror game by David Szymanski, the developer of DUSK and The Moon Sliver, who also wrote its music. It came out on Windows in March 2022, on Nintendo Switch in December 2022, on PlayStation 5 in October 2025 and on Android in December 2025; the Switch and PlayStation 5 versions are published by Ducky Dev Games. The maker describes it as a dread-driven game meant to be finished in under an hour. A film adaptation by Markiplier came out in January 2026.

The setting is a universe where every known star and habitable planet vanished. The survivors on stations and ships are running out of everything, and on a barren moon they find an ocean of blood. You play a convict sent to explore it in the SM-13, nicknamed the Iron Lung, a cramped sub cobbled together from rusty space station parts. Its one porthole stays sealed against the pressure, and a note from the last person sent down calls the mission a death sentence.

All of the game happens inside that cabin. You steer with a few controls, reading your heading and coordinates off the instruments and comparing them with a map that shows only part of the trench. Proximity sensors warn you when you get close to the walls. At each marked site you take a photograph with the external camera, which shows a grainy black-and-white image after a pause. Those photos are the only way you see anything outside.

The horror is in that blindness and in the sound. The hull creaks, the sensors chime, and the soundtrack, inspired by Aubrey Hodges' music for Doom 64, keeps a low hum of unease. The photographs start to show things you would rather not have seen. There is no combat and nothing to fight back with; you go on because you have to.

Next to other underwater horror games such as SOMA or Narcosis, you never walk the sea floor or look out of a window: the whole game is one small room, a map and a camera. Reviewers noticed this; Bloody Disgusting praised its oppressive atmosphere and its sound design, and Destructoid scored it 90.

It suits players who like slow, atmospheric horror that fits in one sitting, and anyone who finds small dark spaces frightening. It has achievements and partial controller support on Steam. Players who want action, a long story or a lot of exploration will find it brief and deliberately limited.

How to play Iron Lung

1. Look at the map in the cabin to find the marked sites and their coordinates.
2. Use the navigation controls to turn and move the sub, watching your heading and coordinates change on the instruments.
3. Listen for the proximity sensors and steer away from the trench walls before you hit them.
4. At each marked site, use the camera to take a photograph and wait for the image to develop.
5. Photograph every marked site on the map to finish the dive.

Tips

• Move slowly and correct your heading often; it is easier to stay off the walls than to back away from them.
• Check your coordinates against the map after every turn so you do not lose track of where you are.
• Wear headphones; the proximity sensors and the sounds of the hull are your best warning of what is near.
• Play it in one sitting with the lights off; it is short enough.

Questions