In 1982, Steven Spielberg and Melissa Mathison wrote a treatment for an ET sequel, called "Nocturnal Fears," that featured evil aliens and the return of ET as savior; Here is a chunk of it:
The spaceship, nestled in the forest clearing surrounded by massive Redwoods, seems to be showing signs of life. Movement can be detected within the ship.
The aliens onboard are EVIL. They have landed on Earth in response to distress signals designating its present coordinates. These aliens are searching for a stranded extraterrestrial named Zrek, who is sending a call for "Help."
The evil creatures are carnivorous. Their leader, Korel, commands his crew to disperse into the forest to acquire food. As the squat aliens leave the gangplank, each one emits a hypnotic hum which has a paralyzing effect on the surrounding wildlife. These creatures are an albino fraction (mutatation) of the same civilization E.T. belongs to. The two separate groups have been at war for decades!
Korel approaches the top of the gangplank and raises his frail arms outward as his yellow heart-light summons his crew back to the Mothership. For a moment the aliens are paralyzed themselves. The tiny creatures eventually look up with their large, expressive red eyes and begin their orderly processional back up into the spaceship.
Inside the craft is a vast assortment of large plants and animal-like beasts in cages of light — obviously specimens from past voyages.
At Elliott's home we see him climbing onto his roof to check E.T.'s COMMUNICATION, which has been anchored down and sending messages into space ever since E.T. left Earth.