The terrapus (plural: terrapi) is a common and dangerous resident of Deepworld. It is a mutant octopus that crawls on land, and it can be found in several varieties, depending on biome and depth. Terrapi spawn underground in several ways: from ragged maws, from behind mined materials, randomly in caves, and from mining (or even moving too close to) a red terrapus egg.
All terrapi make a ratlike squeaking sound and adults take several forms, each with its own type of weapon. Terrapi are generally unfriendly and attack nearby humans. In addition, merely touching one of these irritating beasts will cause damage to the player.
The Pet Terrapus is an exception, being a domesticated version that players can keep as a pet. Like other pets, domestic terrapi are invulnerable to damage.
Each variety of terrapus has different immunities and weaknesses to damage. The elemental varieties (flame, frost, and acid) are immune to their respective type, but weak against the opposite type (e.g., frost against the flame terrapus).
Terrapi get "angry" during Pandora's Box events, following players and moving/shooting more rapidly.
Typically, this mob's number one goal in life is to kill you, but they are very nearsighted and inept at negotiating corners (e.g., they are incapable of keeping track of you if you pass out of their line of sight or make more than one turn in your escape path). As such the normal terrapi are quite simple to either kill or run away from.
The terrapus was the first mob added to Deepworld. It was implemented early on because its crawling behavior was easy to program.
The octopus heritage is Cthulhu-esque.