oh, i wonder why he decided to make the balrog jumping up an animation instead?
It most likely was, also when you re-enter the room, it'd be easier to just do those CMPs then do the FAI so it doesn't waste too much time.
were there two seal chambers?
Yes and no. They're both supposed to be the same place, it's just one Seal Chamber room is where you fight Ballos, and the other Seal Chamber room is for the cutscenewhere you and Curly escape with Balrog. There's also two Arthur's Houses and two Sand Zones (Egg Corridor and Egg Corridor? don't count)
Let's not forget the two balconies and two passages. Pixel had some kind-of creative ways to get around things, other times he simply brute-forced them, heh.
i always thought there was one last cave but there are also two of those!
Well with the egg corridor, it's pretty obvious and as you traverse through, you can infer pretty quickly that it's not the same egg corridor. As for the Last Cave, that's merely a difficulty check, since you have the 2.0 and you're going (assumingly) for the best ending, the challenge fits the difficulty with your new arsenal and possibly new weapons.
if it's your first time playing through though you may only ever think there would be one last cave
The more difficult one is fun since it's on an obviously higher difficulty curve; but don't think that makes the 0.8 version easy, I remember going back at one point and having some trouble since it's readjusted to the 0.8 version. I remember trying to run through it like the 2.0 version, and I got shell-shocked by the level design being, slightly - radically different.
