This game is really cool! Try the demo and if you like it check out the full version!
My review below discusses the game's structure and themes, and while I tried not to spoil specific plot beats, you might pick up on some hints about the nature of the endings and how to reach them. So, don't read on if you want to go into the game with a blank slate.
The game opens with three routes you can play in any order. Roughly speaking, the routes teach you more about the Larkspurs, the family who owned the house; about Evie, the ghost that haunts the house; and about Tabby, the protagonist who is trapped in the house. After completing all three, there is a cool segment where you lay out your beliefs about everything you've learned by answering a series of questions. Your beliefs determine which ending you get; there are three "major" endings, and a variety of "game over" bad endings where the story concludes abruptly, usually with your death.
This is a horror and mystery game, but it's not really a traditional mystery. What if the detective in a mystery story collected all the available evidence, but couldn't actually solve the mystery? The events took place in the distant past, all the major players are dead, and there's so much ambiguity that the best you can do is make an educated guess. You can't gather all the suspects in a room and dramatically lay out the truth. So what kind of conclusions do you draw, and what kind of story do you tell? It's that kind of mystery.
While the major endings give closure, they don't really give you "answers". There is one central mystery which I felt the story explains very clearly, and expects you to understand (you can choose to disbelieve the answer, but I didn't try). Aside from that, pretty much everything else – what happened to most of the Larkspur family, the nature of the entities in the house, the events of the protagonist Tabby's childhood – is unexplained or presented with a healthy amount of vagueness.
This is presumably on purpose, because a recurring theme is Tabby's frustration with "paranormal investigation" and "true crime" media – how the stories they tell are often conjectures based on flimsy and ambiguous evidence, and those conjectures paper over the lives and experiences of the victims. I think 77 Oleander wants you to realize that the stories it's telling you are messy, complex, and human; they're mysteries, but not the kind you can wrap up in a neat bow and claim you've solved. 77 Oleander wants you to wade through the ambiguity and draw your own conclusions, but it stops short of letting you confirm all those conclusions, because getting the "right answer" isn't the point.
(As an aside, I'm noticing strong parallels with the visual novel Umineko as I write this.... Umineko tackles similar themes, but in more of a pulp/fantasy style, presenting you with an Agatha-Christie-esque island mansion murder mystery that was purportedly commited by a witch. 77 Oleander kind of feels like a modern, slightly less fantastical take on this aspect of Umineko, replacing "witches and magic" with "ghosts and hauntings", and criticizing modern paranormal podcasts instead of.... whatever people in those circles were doing in the 90s and 00s? Also, something I find really interesting is that two of 77 Oleander's major endings have prominent red / blue color motifs, which are also important colors with specific meanings in Umineko. Hmm....)
The three major endings actually branch moreso based on your beliefs in the supernatural, as opposed to your beliefs about the human elements of the story. Did these people die in an accident, or were they murdered? That's not really important. Is the malicious entity that keeps killing you a ghost or a demon? Surprisingly, this actually matters. Is Evie a real ghost, or are ghosts a bunch of bullshit, and she's some kind of hallucination? That matters too.
That's because 77 Oleander isn't just about ambiguous unsolvable paranormal mysteries. It's about how to talk about those mysteries respectfully without trampling on the victims at their center. I think what the game wants to say is that you can't do that, or at least it's very difficult, without talking to the victims themselves. Without their input, you're always just scribbling over someone else's life.
77 Oleander presents a strange hypothetical: What if you could meet the ghost at the center of a haunting, and hear their version of the story? What if you could tell a ghost story not for the sake of the living, but "for the sake of the ghost"?
This interacts in an interesting way with the themes of ambiguity and unanswerable questions – I mentioned earlier that there's essentially only one major mystery in the story with a clear answer. But this answer comes from a ghost! So, can you trust the answer? I think the game really, really wants you to trust it. It seems outright cruel to me not to trust it. I think the game is saying, "Only the dead themselves can speak with authority on their own lives!" Paranormal podcasts by randos shouldn't have the final say!
So that's my feelings about the game's overall story and themes. Well, I also want to mention that I liked the moment-to-moment writing a lot too. There's a fair amount of levity and humor to balance the more tense or upsetting scenes: the awkward flirting between Tabby and Evie, the painfully accurate unscripted podcasts, Tabby's disdain for stupid Ghost Adventures bullshit like EVPs and spirit boxes. The presentation is great too! There are a few really bombastic action sequences that are a joy to read and watch. The music and visuals are excellent, and set the mood well both for quieter scenes and more intense scenes.
Finally, there is a nutcracking dog statue that is really cute. I really liked seeing the dog. You even get to give it a name. So, you should buy the game.