I've been struggling with trying to draw Ridley since Metroid 1 came out. He's a tricky bastard, how does that mouth and neck work? It occured to me that I had always tried to change his appearance into something 'more cool and buff', so this time I tried to stray pretty close to the sprite instead.
I think the crazy neck-mouth does add a certain charisma. He's quite a bit different in the manual, with three eyes stacked upon each other and trunky snout of some sort. Much of the artwork in the manual seem to correspond poorly to the ingame sprites. The Kid Icarus manual was much better from that viewpoint.
Some similarities between Alien 1 and Metroid 1:
- Fossilized guys sitting around.
- Ridley might be named after Ridley Scott, and is somewhat similar in design to the Alien.
- You encounter and fight a dangerous alien lifeform.
- This is a real long shot, but in Kid Icarus (aka Light Myth: Parthena's Mirror) had several enemies named after musicians. The big flying mouth is called "Mick", possibly a pun on Lick and Mick Jagger (who has a big mouth). There's also an enemy called Collin, and around it circles enemies which might be called Filling in the japanese version. Phil Collin performed a duet with a certain Phil Bailey around the time Kid Icarus and Metroid were made. Bailey is a part of a famous Metroid password , but it doesn't appear to be hard coded so it's probably a coincidence.
- The female protagonist strips in the end, also revealing that her hair style and hair color is similar to that of Ripley. I think they intended for it to be close to black (like Ripley's), but that wouldn't show against the black space so maybe they made it brown instead. Actually, given how much the NES palette can vary, it's quite tricky to decide just which color her hair is. She could be a red head too, but she's certainly not blonde. The hair also appears to be wavy in the ending graphics, but straight ingame.