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Subnautica Wiki
This article is about the Survival Knife as it appears in Subnautica. To see this subject as it appears in Below Zero, click here.
This article is about the Survival Knife. You may be looking for the Thermoblade.


Weapons were removed from standard survival blueprints following the massacre on Obraxis Prime. The knife remains the only exception.

― PDA, Dialogue


The Survival Knife is a basic tool crafted by using the Fabricator.


The Survival Knife's main function is to procure samples of certain Flora and corals, such as Creepvine Samples and Coral Samples. It can also be used as a weapon, but its damage and range are limited.

By using the Modification Station, the Survival Knife can be upgraded to the Thermoblade.

If a Bleeder latches onto the player's arm, the player can use the Survival Knife to hit the Bleeder.


Silicone Rubber.pngTitanium.pngArrow-right (1).pngFabricator.pngArrow-right (1).pngSurvival Knife.png


Survival Knife.pngBattery.pngArrow-right (1).pngModification Station.pngArrow-right (1).pngThermoblade.png



  • Obraxis Prime is a reference to one of Subnautica's developers, Scott MacDonald, who goes by the alias of Obraxis.
  • One upgrade that was intended for the Survival Knife included adding poison damage to the knife.
  • There was originally a second upgrade for the Survival Knife, called the Hardened Blade, but it was removed when durability was removed.
  • Survival Knife animations that were never implemented can be viewed here.
  • The Survival Knife originally had durability, but it was removed due to it being deemed useless.
  • The Survival Knife is capable of killing a Lava Lizard in ten slashes, whilst the Thermoblade is incapable of dealing damage to them.
  • The Survival Knife was going to be crafted with 1 Metal (Metal was replaced by Titanium) and 1 Emery. The Emery was replaced with Silicone Rubber when it was cut.