The Green Tentacle is one of Dr. Fred Edison's two pet tentacles along with the Purple Tentacle but it is more friendly and less evil than the latter. He loves music and plans to have a band named Green T and the Sushi Platters . Their origin is unknown, but obviously derive from one of Dr. Fred's experiments. Possibly it belonged to the pet octopus of the Biology Department. Chairman Prof. Dilkmore had put a wanted on the College's bulletin.
The Green Tentacle is seen in the second story of the Mansion, hungry, and wants food but he prefers a Bowl of Wax Fruit and Fruit Drinks. After that, he can be found in his room.
His room has a poster reading "Disco Sucks", but is excluded from the NES version as it seemed offensive.
Green can play an important role with Syd and/or Razor; the kids can give him the Cassette Tape recorded with their own music. Green will listen to it and then leave its own Demo Tape on the bed, which can be used to have a Contract by Mark Eteer. With this, he becomes the kids' friend and helps them to pass its Purple brother.
Although friendly, Green can also be dangerous to the kids: if a kid plays the tape of "tentacle mating calls" in its room, Green will move towards the kid and attempt intercourse, resulting in death.
Green will also be upset if Syd or Razor make a contract with Mark Eteer with their own music. If they show Green their contract, he will be so jealous that he kills them.