Ridley wasn't mechanical in Super Metroid because it was made before the prime series. Kinda sucks when the developers forget to tell us why. I'm guessing they cloned Ridley. Same with all the Space Pirates; they have to respawn somehow, now do they?
Second favorite moment: I don't know why, but it's the scene in MP where Ridley flies over you in Phendrana Drifts. It was absolutely beautiful!! I almost shed a tear just because of how magnificent it looked! It felt sooo real!!
Second favorite boss: The nightmare. Yeah, it wasn't as epic as seeing a 3-D boss, but the way it enters, the music, the time slowing down. It was an absolute blast to fight! Beating him on a 1% run wasn't easy either. Pretty much the same reason as Kongfucius.
Third favorite moment: Fighting Rundas for the first time. I still didn't get used to the controls yet, and I was still really sucky and didn't know how the game works. Rundas was a pain to aim and shoot at. I sucked at ripping off his armor too. Seeing Rundas' attacks were beautiful. I absolutely love ice (reference to my favorite bosses and cutscenes). When you actually spend time to fight Rundas, it's actually really, really fun! Later on, I usually beat him in 20 seconds or less. I never died against him because his attacks were so weak. If he was in Gandrayda's place, with more HP, stronger attacks and such, he would be hands down my favorite boss. I'm just saying fighting him for the first time was extremely exhilarating because it seemed difficult.
Third favorite boss: Sheegoth Adult. It looks badass. If it had more attacks, it would be even more badass. It also has a specific weak spot when you first fight him. The next encounters were easily handled by the Plasma Beam. Overall an excellent addition to the game. Being difficult to handle at first, but easily handled later. Did I mention he's badass?