LordCephy: Would you say that it is still worth getting Mary Skelter: Nightmares considering that the GOG page mentions that Mary Skelter 2 comes with the remake version of the first game?
I think it depends.
Both games have more or less the same genres:
-first person dungeon crawler
-turn based JRPG (but with a caveat you will notice as you play)
-psychological horror (and has very few jumpscares, most you grow used to or that you know something bad's coming already so when the jumpscare happens, it'll be hardly shocking at all)
-visual novel
-ecchi
But while the og is more comedy-oriented (not by much, but it's noticeable), MS2 and the extended ending of MS: Nightmares are more drama and romance-oriented (specially the drama part).
And gameplay-wise, the og version is easier, and if it has trophies/achievements and they are the same as the ones from the PS Vita version, you can get most during the main plot mostly by doing all the optionals you can find (they aren't hard to find), and the achievements you may miss are rather easy to get done. And story-wise, I think it works very well and, while it doesn't have a groundbreaking story, it's actually one of the best I've seen in an Idea Factory game.
Meanwhile, the prequel and the remake are much harder, and I'm not sure about achievements as the Switch version (the one I played) didn't have them. And at least to me, the retconned plot of this version also works, although it's premise feels very different (more tragic than the og release).
All in all, I'd say both versions are interesting, the og to get an idea of how the game originally was and since it works as a stand-alone title (and it's rather cheap, specially in sales), and the MS2 version because that's the cannon one now.
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Also a heads up: avoid the music intro that appears before the start menu in MS2. The more I played the game and saw that intro, the more I noticed how much it spoils the entire game, even though I didn't understand Japanese. (kinda sad tbh, since I like the rhythm of the music)