Suits and gear: what keeps you alive below.

The five suits

Suit	Protects against	Rated by
Cooling Suit	Heat, up to the rating in degrees Celsius. Lava and molten metal burn you past it.	The melting point of its shell, and how well the shell insulates.
Pressure Suit	Rock and deep-water pressure, up to the rating in atmospheres. It also holds air in where there is none, for a while.	Hardness, density and toughness of its shell.
Dive Tank	Extra air: more seconds of breath under water and in a Pressure Suit's air.	Elasticity and density of its shell.
Radiation Cape	A share of the radiation dose.	The density of its shell.
Acid Suit	A share of the acid that eats at you.	Hardness, and whether the shell is acid-proof.

The suits go in gear slots 1 to 5. Armour (helmet, cuirass, greaves, boots and shield) has slots of its own: see Armour.

Forging a suit

Each suit is made from three parts, each with its own rules:

• Shell (the body of it): 8 units. It must be a solid of hardness at least 1, or a fibre or hide. Soft things are too soft.
• Liner: 4 units. It must be fibre, hide or an insulator.
• Fittings: 2 units. They must be metal.

Its durability is 300, plus 500 times the shell's toughness, plus 100 times the fittings' toughness. A suit that is working (in heat, in pressure, under water, in radiation or in acid) loses one point of durability a second. In a hot liquid the cooling suit loses five a second. When durability runs out the suit is lost and you are told it broke.

What each rating means

• Cooling: the heat it holds off is the shell's melting point times a factor for how well it conducts heat (a poor conductor insulates better). A liner that is an insulator adds 60 degrees, another liner adds 30, and a very elastic liner adds 20 more. Without a cooling suit you are protected up to 30 °C.
• Pressure: atmospheres held = (hardness times 90, plus density times 12) times (0.5 plus toughness). Without a pressure suit you are protected up to 30 atmospheres.
• Dive Tank: seconds of air = 40, plus 60 times the shell's elasticity, plus up to 60 more for light shells.
• Radiation Cape: the share of the dose blocked is 1 minus e to the power of minus density over 6. Dense metals block more.
• Acid Suit: a shell that acid cannot touch (acid-proof, such as Vitriolite or Waxbark) keeps off 70 plus 4 times its hardness, up to 97%. Any other shell keeps off only 3 times its hardness, up to 25%.

Where each suit goes

Depth brings heat and pressure, so each layer of the planet asks for better materials. The rough guide, from the planet's own layers:

• The crust: copper and iron suits cover it.
• The mantle: ceramic and steel suits.
• The outer core: tungsten suits.
• The inner core: hexaferrum or Coreforged alloys.

The Strata Gauge on your screen shows depth, heat and pressure, and turns red when they beat your gear. See Going deep for the whole descent.

Air without a planet's air

Where there is no air to breathe, your breath runs down at one second a second. A Pressure Suit slows this a great deal: the better the suit, the longer you last. Roughly, a cloth suit gives you about 50 seconds, leather about 60, stone and wood 70 to 80, copper 110, iron 120, steel 140, tungsten 150 and Nova Alloy 180. A Dive Tank adds to each. A suit that is worn down leaks faster, and up to two and a half times faster just before it gives out. The Acid Suit and the Radiation Cape do not change this.

Other things that wear gear

• Lava and hot metal burn you for about 30 health a second unless your cooling suit is rated for them, and burn the suit's durability at five times the normal rate.
• Acid eats at the suits you do not have an Acid Suit over. An Acid Suit wears down in acid itself.
• Blows that land on you also wear armour. See Armour.

Tips

• Take a cooling suit and a pressure suit before you dig past the crust.
• Carry a spare suit: a worn one can break on you in the middle of a dig.
• Choose the shell first. The better the shell, the better every rating.
• For a long trip in space or under water, the Dive Tank adds real time to your air.

← Back to the wiki · Last updated 25 October 2026. Mantlenaut is in alpha, so things change.