Casualties: Unknown Guide
Last updated Unofficial fan guide
A punishing 2D cave-diving survival sim: you play a disposable lab-made creature sent down through 11 layers of an alien planet to recover lost cargo, managing a detailed body simulation (limbs, blood, heart), hunger, thirst, temperature and mood while crafting from what you find.
Made by Orsoniks and published by Oro Interactive, version 1.0 came out on Steam on November 9, 2026. The full game lists at $22.99 USD and had a 15% launch discount ($19.54) when checked on 2026-11-14; the developer announced regional pricing and bundles. The Steam version is Windows-only; Mac and Linux are not listed. There is no mobile version. Linux players report running it through Proton or Wine.
On 2026-11-14 the Steam store showed English reviews as Overwhelmingly Positive (97% of 1,848). The app API reported 3,066 total recommendations across languages.Not yet confirmed A free Steam demo (app 4576510) covers 5 of the 11 layers and stays on demo version 7.0.1; the developer said it will not be updated beyond small text fixes. The older itch.io prototype is pay-what-you-want.
Facts checked against game version 1.0.2. Latest patch at time of research: 1.0.2 (2026-11-14).
Everything in this guide
Beginner's guide →
First-hour priorities, survival basics and the mistakes that end runs early.
Layers →
All 11 layers in order: hazards, creatures and what you can find in each.
11 layers
Items →
Materials, medicine, food, tools and weapons, with what each one does.
290 items
Crafting →
Every recipe in one searchable table: inputs, INT needed and crafting tab.
137 recipes
Conditions →
Status effects and causes of death: symptoms, causes and how to treat them.
41 entries
Creatures and hazards →
Every enemy, trap, plant and crystal: health, what it drops and which layers it's in.
94 entries
Liquids →
All liquids from clean water to L.R.D. serum: what they do, value and recipes.
75 liquids
Achievements →
All 40 Steam achievements, how to unlock each one and how rare it is.
40 achievements
Characters →
Experiment, Milky and Dune: stats, quirks and how to unlock them.
Endings →
How to reach the bio-pod, escape and Mercenary endings (spoilers).
Patch notes →
What changed in 1.0, 1.0.1 and 1.0.2.
FAQ →
Price, demo, platforms, multiplayer, mods and save files.
Layers at a glance
Layer guide →You go down through ten layers to reach the cargo, then climb the short eleventh layer back to the surface.
- 1Gravel LandsCold starting layer of small linked caves of stone, gravel, soil and clay with groundwater pools; short falls and light from holes in the background.
- 2Deeper Gravel LandsDarker continuation of layer 1 with no light holes, concrete beams and lumalgae pools; tougher traps appear.
- 3Dried DesertSpacious sand and hard-stone caves with tall drops and deadly traps; groundwater is scarce and viscous oil pools are common.
- 4WastelandRadioactive fallout layer with no enemies but sound cannons, toxirock, spent fuel and the traps of the desert.
- 5Overgrown DepthsJungle layer full of edible plants, sap and water, where combat with thornbacks and the huge elder thornback is the main threat.
- 6Frozen ChasmIce layer where the cold itself is the main killer; you hop between heaters, heatferns and life pods to stay warm.
- 7Fungal PoolsFungus layer with constant rain; sleeping while wet outside a life pod can freeze you to death.
- 8Crystalline HollowChaotic terrain of glowing crystals with huge drops; crystals can have random special properties and flying Manifestations attack.
- 9Geothermal VentsExtremely hot layer with magma; air pressure starts to build in its lower half.
- 10Where We Must ReachDeepest layer holding the cargo; pressure keeps rising while you stay, and its traps mix those of earlier layers.
- 11Crimson AscentShort final layer: the drill pod breaks and you climb up to the surface; the exit is at the top.
Quick answers
›Is Casualties: Unknown free?
No. The full game costs $22.99 (15% off at launch). The Steam demo (5 of 11 layers) is free, and the old itch.io prototype is pay-what-you-want.
›Is the demo still updated?
No, the demo stays at 7.0.1.
›Is there multiplayer?
Not officially; it is single-player. An unofficial BepInEx mod called Casualties Together adds co-op.
›Is it on mobile?
No. Steam lists Windows only and no source mentions an iOS or Android version.