Terachnoids were a highly intelligent race, native to the planet Terachnos. They had pink skin and an unusual head-to-body size ratio and often wore glasses and other attire that showed off their intelligence. Some members of the race also carried portable consoles with them. The sages of the Terachnoids were apparently the most intelligent. The highest concentration of Terachnoids were in Axiom City.The Terachnos based-company Pollyx Industries' employees were believed to be made up of purely Terachnoids due to the species' apparent ignorance of the intelligence of other lifeforms. Later when Dr. Nefarious took over Pollyx Industries the Terachnoids were constantly under guard. Nefarious's mercinaries patrolled the whole area which annoyed the Terachnoids greatly.
Terachnoids were not entirely selfish. They ran companies that helped others with tech support, although the consumer was usually made fun of due to their lack of knowledge in the technological field. That seemed to be the only business outstide of Terachnos except for Vullard trade. Some Terachnoids had special ships and delivered supplies to the Vullards.
With the Terachnoid's high intelligence also came the love of technology. They usually spent a lot of their time playing a massive online role playing game that they seemed to be addicted to. When Ratchet and Alister Azimuth stormed into Pollyx Industries in an attempt to find the Obsidian Eye, Ratchet confronted the Terachnoid at a central computer terminal. Before attacking, the Terachnoid tried to intimidate him by saying that he was "a level 60 wizard, with melee ability."
It is also seems that the Terachnoids only seem to enjoy associating with people of their race, as they see any other species as less intelligent than them. There is a possibility that Terachnoids were bullied many times throughout their lifetime.
When in Axiom City, Ratchet can hit them with the OmniWrench Millenium 12, causing them to sometimes say: "It's like high school all over again."
Places inhabited by Terachnoids
- While most Terachnoids had only two eyes, some had five.
- The Terachnoids were awarded "The Brainest Race In The Universe" for 3000 years in a row. It is also "The Weakest Race In The Universe" for 4000 years in a row.
- Terachnoids could be seen working in Nefarious Space Station, but some were simply holograms presumably located in Pollyx Industries.
- The smartest Tercahnoid on record, G'Narlax Frahm was born with seven-and-a-half brains.
- A Terachnoid Juice Maker was the 3rd most complicated piece of machinery in the universe with over 3 trillion moving parts.
- The Agorians hired the Terachnoids to work at the Agorian Battleplex because, according to Mac, the Agorians "are a bit short-changed in the brain department" so that they hired them to do their thinking for them.
- A challenge in the Agorian Battleplex was created due to the fact the Terachnoids told the Agorians that Ratchet made fun of their legs. Ratchet had 3 minutes to survive in the arena.
- It is implied that the Terachnoids are also skilled with magic, as Captain Darkwater used an ancient incantation originating from their species to forever bind his soul to his body in order to protect the Fulcrum Star.
- Ratchet & Clank Future: Tools of Destruction (first appearance)
- Ratchet & Clank Future: Quest for Booty (mentioned only) 
- Ratchet & Clank Future: A Crack in Time
- Ratchet & Clank: All 4 One (mentioned only)
- Ratchet & Clank: Into the Nexus