Maniac Mansion II: Day of the Tentacle

Day of the Tentacle, also known as Maniac Mansion II: Day of the Tentacle, is a 1993 graphic adventure game developed and published by LucasArts. Five years after the events of Maniac Mansion, Purple Tentacle—a mutant monster and lab assistant created by mad scientist Dr. Fred Edison—drinks toxic sludge from a river behind Dr. Fred's laboratory. The sludge causes him to grow a pair of flipper-like arms, develop vastly increased intelligence, and have a thirst for global domination. Dr. Fred plans to resolve the issue by killing Purple Tentacle and his harmless, friendly brother Green Tentacle, but Green Tentacle sends a plea of help to his old friend, the nerd Bernard Bernoulli. Bernard travels to the Edison family motel with his two housemates, deranged medical student Laverne and roadie Hoagie, and frees the tentacles. Purple Tentacle escapes to resume his quest to take over the world.