His death was announced by Mario Caligiuri of the Calabria region's cultural affairs council.

Mr. Rambaldi was adept at designing monsters, from the terrestrial to the decidedly not. His expertise in techniques including puppetry and mechanical and electronic engineering allowed him to breathe life into the most fantastic movie creatures of the 1970s and '80s.

He designed and built an eyeless animatronic head that realized H. R. Giger's parasitic beast in "Alien" and the benign, musical aliens of Mr. Spielberg's "Close Encounters of the Third Kind." He also collaborated on animatronic masks, suits and a 42-foot-tall ape for "King Kong." But his crowning achievement was "E.T."

In "E.T." an alien is marooned on Earth, where he befriends a lonely boy named Elliott who helps him to contact his home planet and return to space. For the movie to succeed, audiences would have to identify with, and love, a prop.

So Mr. Rambaldi used steel, polyurethane, rubber, and hydraulic and electronic controls to create an alien so ugly it was beguiling, with outsize eyes based on his cat's and wizened skin (in some scenes E.T. was played by an actor in a suit). The alien was capable of 150 separate moves, like wrinkling his nose, furrowing his brow and extending his neck.

"Carlo Rambaldi was E.T.'s Geppetto," Steven Spielberg said in a statement on Friday.

The movie has grossed nearly $800 million worldwide, proving that special effects could endear as well as titillate and horrify.

"The success of 'E.T.' means that it no longer is important that you have Marlon Brando or John Travolta," Mr. Rambaldi told The New York Times. "If the special effect is created very well, most people don't think whether it's mechanical or not — they're thinking about the story."

Carlo Rambaldi was born in Vigarano, Italy, in 1925. He attended the Academy of Fine Arts of Bologna and had a successful career as an artist before he started working on films. His first creation was a fire-breathing dragon in the 1957 Italian film "Sigfrido."

He worked on gory horror films in the '60s and early '70s, including "Andy Warhol's Frankenstein" and "Andy Warhol's Dracula," as well as Dario Argento's thriller "Deep Red."

The producer Dino de Laurentiis reached out to Mr. Rambaldi for help with the special effects in "King Kong." He moved to the United States in the mid-1970s and stayed more than a decade, working on films like David Lynch's "Dune" and Richard Fleischer's "Conan the Destroyer."

His last credited work was "Primal Rage," a 1988 horror film directed by his son Vittorio.

Mr. Rambaldi was a traditionalist who disliked the advent of computerized special effects.

"The mystery's gone," he told an Italian news service. "It's as if a magician had revealed all of his tricks."

Information about Mr. Rambaldi's survivors was not immediately available.

Mr. Rambaldi was susceptible to the charms of his creations, especially "E.T.," even though he knew the tricks behind them.

"When I finally saw the finished movie," he said, "even I cried a little."