spoilers for a game that I think you probably shouldn't play. cw: brief mentions of suicide, cannibalism, rape, incest
genuinely, I struggle to find the words for my thoughts on this game. the legacy of this game looms over a lot of otaku media. it's not the sole genre-shaking titan of its era, but it sure is a factor in a lot of things; the most obvious descendants are other visual novels mimicking its multi-route + true end structure, but it appears in less obvious ways in other mediums such as manga (the world god only knows' author literally cited yu-no as an inspiration, for example)
there's a lot of interesting things to mention about this game! the insistence that the timelines are physical spaces turns the entire text of the game into a sort of dungeon crawl, with key items and varying choices of timing opening new paths to follow, is a fascinating one. the textual use of parallel routes which you can hop between is also always a favorite of mine.
but when it comes to the story... every woman is treated cruelly by the text. one is shot, electrocuted, or dropped to her death, fated to an inevitable end no matter what you do. the protagonist's actual mother and stepmother both take their lives (as does his eventual wife). a pet lizard grows up into an anthropomorphic dragon girl only to be used as transport and eaten as an emergency food source. one woman was only spared from the textual proof of being raped by the mercy of the remake by which I played this game not having any explicit sexual content.
what is there to say? every woman with a name falls over herself to make herself important to takuya, and suffers for it. every man is a scumbag on a sliding scale of our "lovable scamp of a pervert" main character to an evil specter from beyond dimensions who keeps hypnotizing people into violence both standard and sexual antagonist.
the game was tolerable, with foibles I found interesting enough to contemplate, as I worked through the bulk of the game, but once I hit the Other World chapter, it was a straight shot down the toilet for the vibes.
the eponymous yu-no is the main character's biological daughter, born of a union between him and a woman in this other world... where children grow up extraordinarily fast. four years pass and she's a young teen, and after several months apart, she finishes becoming an adult in form, if not in mind.
and the entire time, she is uncomfortably attached to her dad. a four year old girl who looks like an adult, who just really really really wants to fuck her dad in place of her mom. a grim mirror of takuya's interest/pursuit in his stepmom from the first arc of the game.
the second arc, in the other world, was originally planned to be more involved, literally mirroring and interacting with the first arc's world and routes, but... it's linear, its characterization of the women it focuses on is severely flattened out relative to the girls that appear in the first arc... and again, you unavoidably end up with takuya fucking his daughter. there's an apocalyptic threat, and journeys across the desert, and interdimensional peril, but it's all in service of a half-cocked revenge plot against a god-emperor who turns out to be the support staff for a literal deus ex machina.
the last thing you do is use yu-no as a save point so when you go back to takuya's own time, you can warp out to the point where you saw her at the start of the game, and takuya joins her as they seek out the root of all causality, and together they spend eternity watching cause and effect unfold.
it's really not all that interesting. bioshock infinite talking about "there's always a lighthouse" type thing. but maybe that's me being soured on it because I've seen what this has influenced.
I'd compare this to mushoku tensei. for those of you who are unaware, I'm quite fond of isekai media, and mushoku tensei is often well-regarded as a grand-daddy of isekai anime... which is kind of horseshit, but whatever. it's also just got rancid vibes all throughout, and I'm really not fond of it for that reason. despite that, I find it useful to examine these touchstones because, often, knowing what lies as the cause of inspiration leads to being able to see phantoms of these things in other works. mushoku tensei's myriad creative decisions become jumping-off points for other savvy writers to set themselves against and produce better art for it, and I believe yu-no is in a similar category. the decisions made in producing this game are... whatever. I'm ultimately more interested in using it as a reference point for games that are actually worth most folks' time.
if I had to be the one to bring yu-no to your attention, I would not recommend playing yu-no. if you care enough to be considering it as a historical game, the remake is fine and includes some excessively helpful hint functions to keep things brisk. if you want more of a rundown of the game without playign it yourself, I would recommend reading this essay because it will give you plenty.