Copper Lung

Seal yourself inside a riveted copper submarine and descend into an ocean of blood.

Build a rocket, fly to the AT-5 research station, and lower your submarine through the moon pool into the Blood Ocean: a pitch-black sea where you can barely see past the glass. Navigate by sonar, photograph what you find, salvage sunken submarines, and survive the Blood Eels that hunt in the dark.

🚀 Getting There

• Craft the AT-5 Rocket, a Launch Pad and a Launch Console, and fuel the console with Rocket Fuel.
• Stand the rocket on the pad, climb in and press V to launch. A submarine parked nearby comes along as cargo.
• At AT-5 station, dock the submarine on the moon pool grate and the winch lowers you into the blood.

The rocket is the only way into the Blood Ocean, and the only way home.

🛳️ The Submarine

• A fully modelled cockpit: you see the ocean only through the bow window.
• Sonar shows fossils, the station, Blood Eels (with their heartbeat) and your contract targets.
• Headlight and flash lamp: tap to startle an eel, or hold for 2 seconds to overcharge a flash that burns them.
• Camera: take grainy photos of the deep and browse them in the gallery.
• Depth gauge, hull gauge, and a viewport that cracks and runs with blood as the hull fails.
• Repair the hull with Iron Ingots. Hit the sub to pack it into an item; it keeps its upgrades, damage, paint and name.

🔧 Upgrades & Customisation

Five upgrades, each visible on the hull:

• Reinforced Hull Plating: hull 45 → 75
• Flash Capacitor: faster flash recharge, stronger overcharge
• Sonar Amplifier: sonar range 40 → 80 blocks
• Salvage Claw: longer salvage reach, and left click strikes Eels with the claw
• Turbine Engine: much faster top speed

The Paint Kit lets you repaint the copper with any colour from a colour wheel, change the lamp colour, and put your sub's name on its brass name plates.

🐍 Blood Eels

Huge, pale eels with mouths ringed in needle teeth. They stalk you, roar to cloud your vision, then charge and bite the hull.

• Five flashes drive one away.
• Fight back with overcharged flashes and the Salvage Claw.
• Kills drop Blood Eel Teeth and Hide straight into your inventory, used for the Fang Sword and Blood Eel Hide armour.

🩸 The Infection

The Blood Ocean infects you: swimming in it, a breached hull, or an eel bite. Watch your vision redden, your hands lag and your body change. Fight it with Antiseptic, the Decontamination Shower, the Medical Scanner and the Infection Monitor.

📟 Research Terminal & Contracts

The station's Research Terminal holds the field manual, research notes and recovered logs, plus quests and repeatable contracts:

• Fossil Survey: photograph a marked fossil
• Wreck Salvage: reach a marked sunken submarine
• Wreck Documentation: photograph a marked wreck
• Depth Sounding: take the sub down to a marked spot on the sea floor
• Eel Deterrence: find an eel yourself and drive it off

Get near a sunken submarine to recover its pilot's last log, and salvage its loot with O.

🎮 Controls (all rebindable)

⚙️ Config

Server owners can turn natural eel spawning off and change Blood Eel health and bite damage in config/copperlung-common.toml.

📦 Requirements

• Minecraft 1.21.1
• NeoForge 21.1.x
• JEI is optional (but recommended): if installed, it adds info pages for the mod's items.