This article is about the Deep Shroom. You may be looking for the Acid Mushroom.

The Deep Shroom is a hazardous flora species found in abundance in the Blood Kelp Zones and their caves, in small clusters, and in the Lost River and the Sea Treader's Tunnel Caves. It is a relative of the Acid Mushroom. It is used as a raw material in the manufacturing of Hydrochloric Acid.

The player can pick up Deep Shrooms by hand. The player can also strike one with a knife to destroy it and collect four Deep Shroom Spores, which causes 8 damage to the player and surrounding flora and fauna due to acid being released into the water.

The Deep Shroom and its spores can be planted in an Exterior Growbed or an Alien Containment.


The Deep Shroom appears as a stout mushroom with a white cap, becoming pink towards the centre, and a dark grey stem. It is similar in shape to its relative, the Acid Mushroom, as they share the same model but have different colorations.


Like the Acid Mushroom, the Deep Shroom possesses highly acidic compounds in its flesh that leach into the water if its skin is pierced. As such, harvesting spores from the Deep Shroom with a knife triggers its acidic flesh defense, dealing 8 damage to the player and surrounding flora, fauna and structures.

It is possible for a Deep Shroom being destroyed to cause a chain reaction, damaging other surrounding Deep Shrooms enough so that they burst as well. This chain reaction can instantly kill a player, wreck a Seabase or heavily damage vehicles, so it is advised that the player separates Deep Shrooms before the harvesting their spores.

Deep Shrooms will shrink upon fluctuations in the local water pressure such as if the player approaches them, and will return to their original size if the player holds still or leaves the area.

Uses in Crafting

Deep ShroomDeep ShroomDeep ShroomSalt DepositArrow-right (1)FabricatorArrow-right (1)Hydrochloric Acid

Energy Value

Deep ShroomArrow-right (1)BioreactorArrow-right (1)Energy×50

Data Bank Entry

Deep Shroom-0

A discolored relative of the acid mushroom, adapted to low-light conditions. Considerably more acidic that its shallow-dwelling cousin, it may have applications in advanced fabrication.

Assessment: Can be processed into hydrochloric acid



  • The difference in coloration between the Deep Shroom and the Acid Mushroom is an evolutionary mechanic, which is also found in many other flora and fauna species in Subnautica as well as many real-life animal and plant species, in which there is a loss of pigmentation due to restrictions in available nutrients.
  • Some Trello notes refer to the Deep Shroom as the Ghost Mushroom.