Without her emotional display of waking from her nightmares it would not have been believable that she would want to face the monsters that dominate her sleep in real life again. In addition, she knew she was betrayed by Weyland-Yutani as a crew member of the Nostromo and that she would have to trust them again that she would not be expendable. After seeing this movie so many times, I got this deep sense that many of the Marines sent in to rescue the colonists were absolutely expendable and I often wonder if they didn’t mean for Ripley to die as well.
He is a monster in the sense that he is the Frankenstein monster of his own making. He is a Godzilla of his own design that can tear down buildings in the blinking of a rapid-eye-movement. He is an unstoppable force that even reality cannot defeat because he changes reality. The only way to defeat him is to keep him awake and undreaming.
There seems to be a lot of magnetism and light needed for time travel here. Well, I give up. What’s that about? If I lay on a bed of magnets in the sun, will I get younger?

