Lava Lizard
The Stalker is a predator hostile to the player, other life forms and even sometimes even other Stalkers.
Stalkers can be found in multiple Biomes, predominantly in the Kelp Forest.
They appear to have developed an interesting behavior. Stalkers seem to be fond of Scrap Metal, pick it up and gather it in one spot. This can lead to dangerous situations for an unaware player finding such a treasure.