Fauna

Fauna are life forms found all over the world of Subnautica, from the deepest darkest depths of the secretive Lost River to the vibrant Safe Shallows.

There is a large variety of Fauna, ranging from the minuscule, cave-dwelling Rockgrub, to the colossal Sea Dragon Leviathan that spews molten minerals from its mouth. Fauna on Planet 4546B are capable of enduring and adapting to various environments, although unable to thrive due to Carar.

Fauna on Planet 4546B only have one gender that is capable of both laying eggs and fertilising them. Two parents are still needed in the majority of cases. Fauna on 4546B also have yellow blood.

Trivia

 * Fauna were intended to posses inherent attributes, that would have caused them to exhibit unique behaviors. These included, e.g., "Fertile" (occasionally lay eggs that can be hatched), "Alpha" (attacked the player if other creatures were killed by the player in the immediate vicinity), "Complex" (specimens take longer to scan), "Greater" (specimens are of larger size and weight), ... Whether these attributes are currently implemented or will be implemented in future updates is unknown.
 * As of the Dangerous Creatures update, all fauna have yellow blood. Before this update, fauna had red blood. This is due to the ESRB giving Subnautica a higher rating than expected due to red blood.
 * The Cute Fish is currently the only obtainable pet fauna in development, which is obtainable through the debug console and will only be granted to players whom purchased the early access version or the special edition of Subnautica.
 * If you hold a small animal in your hand when a carnivorous fauna is about to attack, it will eat the animal out of your hand, instead of attacking you.
 * In the very early stages, there was an unused Sandworm that could only be spawned using the console, it would stay in one place under the ground and when the player or an npc was right above it, it would spring up and would do 1 damage but at a very fast rate, the only indication of there being a sandworm is a large mushroom cap that is on the ground. It never had any animations.