On to the next installment. West declared dead? Who the hell names a demon a "Top-Heavy"? Read on and find out...
Year: officially, never given out; but there are no signs that the producers wanted it to take place on some past or the future, so I'll be riding with 1988, because it also fits nicely when the series timeskips later on.
The plot: honestly? Originally, Rick and his girlfriend Jennifer search for shelter for a storm and they find a mansion nearby. They go in, then the door slams, and the next thing we hear are Jennifer's screams. Rick is more than likely knocked-out and then carried someplace underground and only wakes up when the Hell (Terror) Mask attaches itself to him, giving him enough power to crush the hordes of undead roaming the place. After fighting a pretty ample amount of hellish creatures, including the (in)famous Biggy Man, Rick goes back inside the Mansion and ends up in a cathedral built within it, where he fights the satanic Hell Cross. After destroying it, he hears Jennifer scream and rushes to her aid. He finds her surrounded by Deadmen, chiefed by a Top Heavy, which of course were doing something to her. They flee upon Rick's arrival and Jennifer gets up; apparently fine at first... but then she mutates into a hideous demon. Rick has no other choice but to fight for his own survival. In the outcome, the mutation seems to be repressed and Jennifer lies beaten in the ground. Rick holds her, but she turns into a soul after saying "Goodbye" and flies away. Then the previous Top Heavy comes up and taunts Rick. There's a bad idea if I've ever seen one, specially since we're talking about a guy with a Mask that gives him supernatural powers whose girlfriend you just made him kill. Rick jumps to the underground of the Mansion, which seems to be all organic. After being constantly hassled by "Obas", the larvas to the Deadmen found earlier in the House, Rick comes up against a giant heart, called "Mother", that is spawning all the creatures (or at least the Deadmen) in the mansion. He kills it and it gushes out a flood of blood and apparently causes the house to come apart, also setting it aflame in the proccess - so it appears that the House was like a living entity as well. Rick is on his way out when many demons on fire come shrieking in pain jumping frantically around. After making his way past them, Rick finds a cross carved in the ground. A spirit of the mask leaves Rick and possesses whatever is underground - and a hideous giant head, likewise with two giant hands, comes out of the ground. After Rick destroys it, a spirit in apparent agony leaves the ground from where it formed and with a ghostly moan starts releasing hundreds of smaller spirits - and then it fades away. Then, the mask shatters. Rick is left stunned, the hellish Mansion burning behind him... and then later, without Rick's knowledge, the Mask's remains assemble again and it laughs demonically.
That's the main gist of it - details like the house being set aflame due to the destruction of Mother were given at WikiJP and another Japanese page covering the trilogy (they left Wanpaku Graffiti out, though, but I digress). Years later, though, there would come the PC Engine port, and then things were considerably spiced up - we were given the protagonists' full names (Rick Taylor and Jennifer Wills) and that they were parapsychology majors, researching on Dr. West, who were involved in gruesome experiments and eventually died - that's right, according to the Japanese Wiki, they spill out the beans in the PCE manual just like that. Nothing like "West disappeared, the mansion should be deserted" - West died, that much was known. The West Mansion even already had it's alias "Splatterhouse". West was a world-reknowed authority on Rick and Jen's field, so they decided to investigate it for a University work. However, because of a strong storm, they seek shelter in the Mansion. But really - it's not like the storm heavily factored here like it would in the original story. Rick and Jen wanted to investigate the mansion (regardless that with it's fame they should be pretty wary of doing so), so storm or no storm, they'd be going in anyway. To me this is looking more like trying to concile the original story with the new bits, but I digress. Even if it the first time we've seen West depicted and mentioned was in the PCE manual, and the first time the Mask was named accordingly, there's nothing to say those weren't Namco's plans originally - and that they just didn't have the space to describe such in the arcade release. In-game narrative was also a bit primitive by the time, so, push comes to shove... The manual even provides the monsters who would've captured Jennifer and knocked Rick out; a Deadman and a Top-Heavy, respectively. Then the Hell Mask takes Rick over. It's not made clear if Rick is aware of the mask's name or if the narrator is just informing us of it. It could be either, since it says the mask is legendary. And on Rick's field, he could've easily stumbled upon a paper or two about it.
The fact West is dead also just helps me think that whatever was buried under the cross that the mask possessed may have been intended to be him at first, before the whole "appearance in Part 2" thing came around. Sure, Namco threw in the Mask regenerating itself at the end of Splatterhouse, but they were also sailing on strange waters - games like Splatterhouse weren't really all that frequent at the time. I can only think of the hillariously bad yet also outrageously gory Chiller light gun game released years prior. So I don't think that they were exactly thinking of a sequel (hell, it took them four years to come up with one) and threw that out more as of a means of being the "final scare" of the game - just like many horror movies end with some twist to say that not all is well, sometimes not caring much about the coherence of the narrative (honestly, the Splatterhouse series suffers of this as well - just the check the ending to Part 2. Credits roll, then a spirit zooms in and Jennifer screams. And nothing is made out of it. Hell, the spirit also resembles the one seen in the end of Splatterhouse a lot, and that one was tied to the Mask, so I'm thinking it was the Mask saying "Ha ha! Gotcha! Hey now, I really have to be going to float somewhere else for the next five years. Nice dismembering ghouls with you, Rick. See you next game!").
Also, there's something that could pretty much put to rest the whole Mask Spirits debate: running the text in one translator, it came out as saying that the Hell Mask carries the spirits of the dead. So one spirit could leave the Mask and possess something else, with Rick retaining it in the proccess. Of course, it seems a bit discrepant to me that the other dead sacrificed in order to power up the Mask would be so altruistic as to help Rick destroy evil when they could possess something else and perhaps be free, but I digress. I've yet to see if it's indeed said in plural, but I'm sure hoping it is, because then it's one less gap to fill.
Differences between English and Japanese releases: not much, specially compared to Splatterhouse Part 2 (of course I'm talking plotwise - I figure I don't have to list the differences that aren't narrative related since we're all aware of it - redesigned red mask, Evil Sleep, tombstone instead of cross at the end of the game, etc). The English sources say West disappeared a long time ago and has been unheard from. The PCE manual states blatantly that he lost his own life some time after he had started his monstrous experiments. Ironically, the English version here ties better to Part 2 than the Japanese version itself, even if West himself in that game is supposed to be a zombie. I say that because with West dead and all, it really seems that there is nothing else that thing buried at the outskirts of the Mansion could be. Also, in the English version it says Rick had read about the Terror Mask in West's writings. It sure makes a lot of sense, since the Mask is at the Mansion. But there is nothing to that effect said in the PCE Manual - it just says that is a legendary ancient mask with the spirits of the dead and that it grants the user supernatural powers, and also it's name. So while it's not flat-out denied, you could also argue that Rick is aware of what the Mask is in the English version and came to know it only when it possessed him in the Japanese version.
One could also argue that the Mask being there, that explains where the monsters came from in the first place (and subsequently where they'd be coming from on the sequels), accounting the English version of Part 2, where "Dr. Mueller" is sure there is a connection between the monsters appearing around his mansion with the mask and Rick outright stating that as long as the Mask remains, "it can happen again". But the Turbografx manual itself says that the Mother (not named in the manual) is spawning the monsters into the mansion. So, it doesn't fit.
I think that about wraps up plotwise what there is to be said between the original Splatterhouse and it's two versions. Then, onto the bestiary. The names have been taken straight out from the PC Game Manual. I can't translate the descriptions from the manual itself, as it is beyond my grasp of Japanese and the letters are too small to make out some of the kanji in the scans found in the site, so these were taken from Wikipedia-JP instead. So these, you may want to take with a grain of salt. Under parenthesis are the names given in Splatterhouse US materials.
Deadman (Red Walking Zombies)
Described as a "lower-class experiment body", more than likely because of it's poor endurance.
Green Deadman (Green Walking Zombies)
Still weak, albeit stronger than the standard Deadman.
Common vampire bats.
Top-Heavy (Large-headed Demon)
Upper-class experiment body with a mushroom-based head. The body may be destroyed, but the head will then charge at the agressor.
Hanging Body (Hanging Corpses)
A decomposed corpse, hanged by the neck with a rope. Ocasionally vomits venom and comes down from holes in the ceiling.
Body Eater (Crawling Red Slime)
A huge leech which stays in lumps of flesh assumed to be a nest. When someone alive is detected, they attack it in group in order to feed upon them.
Water Dead (Sludge Monsters)
Experiment body to live in places such as the sewer. Has a great range for it's punches.
The spirit which wanders about on the bridge. When it touches Rick, it drags him and drops him to the river where Water Deads expect him.
A crow that attacks brutally. Flies in a straight line. Absent in the PCE version.
An undead stray dog (apparently a result of manipulation of West's, since they say the dog is 'made a zombie' or 'converted to zombie'). Their favorite meal is a Deadman, ironically, so if you knock one down they'll come out to feed at it's corpse. But if you attack them while they are feeding they will get angry and charge at you.
Nobu (Crawling Slug)
Monster of "curvy-meat". Vomits venom.
A resident of the "mirror world". When Rick is fully reflected he breaks out of the mirror and attacks him.
"Uddei" (Crawling Hand)
I'm honestly at a loss to translate this name... maybe it's referring to a Japanese term even if it is in katakana. It is described as a severed arm with will, that taunts Rick with it's finger and jumps at him to try to bar his progress.
Countless severed heads floating around Evil Cross. They'll keep respawning until the Evil Cross itself is destroyed.
A grudgeful spirit confined to the masterpiece.
Ghost of a beautiful girl. Drops a skull at Rick's head.
Zombie. They'll keep coming back as long as Master Dead is still around to raise them.
A dead spirit which leads and raises the Revival Dead to attack Rick through necromancy.
Obas in incubatory state. It floats around and when it lands, the Oba is fully born.
Oba (Newborn Monsters)
Larva of Deadmen. It attaches itself to Rick doing damage.
Fire Dead (Fire Demons)
Wikipedia says they are Deadman burst into flames. It's very likely. However, the PC Manual doesn't say anything about "Deadman" in it's description of the Fire Dead, but really, I don't see what else they could be. They can't be destroyed.
Enemies not accounted for in the manual and wikipedia but mentioned in the TG16 manual: Chained Corpses and Fire Logs.
Poltergeist (Candle, Knife, Chair, Empty Can, Whiskey Bottle, Picture and Chandelier)
Various furniture is manipulated by an evil spirit's will, and it obstinately attacks anyone alive.
Biggy Man (yep, it's his name alright. "Piggyman" is more than likely a romanization error, due to "PI" and "BI" being awfully similar characters in katakana)
A giant "remodeled" by Dr. West, who imbedded a chainsaw to both his hands. To conceal his horrible appearance, the bag is worn.
A holy symbol possessed by an evil spirit, in turn becoming wicked. It is surrounded by disembodied heads called "Nightmare". Changed to a demonic floating blue head called "Evil Sleep" in the Turbografx version.
Rick's beautiful girlfriend. She is "remodeled"/mutated by the monsters in the Mansion to a hideous monster whose nails can extend.
The heart of West Mansion (yep, they say "OF". So much for Castlevania being the first "creature of chaos" when we're talking about huge places that houses hordes of undead. Suck on that, IGA!). It limitlessly produces Egg Obas.
Hell Chaos (Demonic leader)
The mysterious form the Hell Mask possessed. A giant creature that crawls in the underground of the Mansion. It uses it's gigantic hands and throws rocks to damage Rick.
Well, that should be it about Splatterhouse, right? Wrong. The last page of the PCE Manual caught my eye - it is specifically labelled "ENDING" and has that ominous picture of the Hell Mask's 1st design to go along with the text. Dios translated the text from the manual. And hell, does it do a fine job of causing even more confusion or what. Here's what it says (complete with intact redundance and translation notes):
"The Hell Mask put the cursed Splatterhouse in a cursed slumber of many years.
When Rick escaped from Splatterhouse, the Hell Mask returned to it's place of origin... (TN: it actually says 'returned to the place where it should be')."
So, let's analyze a few things. Despite being put in the "Ending Section", the only way this sentence makes sense is if the Mask had put the mansion in slumber prior to the beginning of the game, most likely after West departed (in both ways). Because there is no mansion left to be put to slumber after Rick escapes, it's fucking burned to the ground. Also, if the Mask had put the mansion to 'sleep' then I'm guessing it woke it up when Rick and Jen got there. So what the hell gives? My friend said he was having a bit of trouble with the first paragraph, so he says that there's always margin for error, but that he says that he's 90% sure of what the text says in that page.
And if the Mask 'returned to it's place of origin', that'd explain how "Dr. Mueller" would be able to find it... despite that we're talking different canons and it later going back to the West Mansion (or what remained of it, you get the gist) again. But that phrase is so ambiguous it can mean anything, as I haven't seen any Japanese materials say the Mask is of Mayan or Aztec (or whichever old civilization you'd prefer) origin.
By the way, not to rain on anyone's parade (especially mine, at that) but do remember that while all that was said on the enemies' descriptions, including West Mansion being alive, is still not 100% proven, even if it makes a whole lot of sense. Because unfortunately, as I said, I had to go by Wikipedia in those descriptions, and while it seems that everything should be in order, we can't rule out people just putting their own theories as stated facts. We'll have to deal with this uncertainty until I get some sort of official confirmation, either be it by some Japanese person telling where they got these bits from (which I once again think might be a gamebook for Splatterhouse) or if Namco themselves answer via the WM Q&A. I honestly think Namco could easily answer those, because even if Splatterhouse is 20 years old as of today, the PC port came not too long ago and there you have it, even if it was not by Namco and stuff, it certainly had a lot of info on the enemies and bosses, including their names and whatnot. I pretty much believe that whichever materials they have for the classic games are just stored up somewhere for referrence, and all they'd need is dust them off and see what comes up on these regards.
Next up: Splatterhouse Part 2, where most of the narrative was changed both ingame and manual-wise when localized.