Cheat Mode
Once you launch Subnatica and get into your world, press [X]+[A]+[RB]+[LB] at the same time to bring up the developer console. Enter the following codes there to activate the corresponding cheat option:
nocost - Make anything without any materials.
fastbuild - Faster building.
Madloot - Free useful items.
Oxygen - Infinite oxygen.
Radiation - No radiation.
day - Set to day.
night - Set to night.
sub Cyclops - Spawn Cyclops.
item [name of item] [amount] - Spawn items.
Spawn seamoth 1 - Spawn seamoth.
nodamage - Take no damage.
biome [name] - Teleport to biomes.
warpme - Teleport to safety.
Allblueprints - Unlock all blue prints.