A fabulous game and one of the godfathers of the "survival horror" genre.
The atmosphere of this game is great. You can truly feel the evil has infested Decerto, from the foundations to the very rooftop. The entire scenery is so strong it truly has a personality of its own, kind of like the Overlook hotel from "The Shining". The camera angels are beautiful, the monsters are scary (especially the Chthonian, the invincible ghosts and the blasphemous entity guarding the main doors) and the creepy books create a chilling and unnerving atmosphere.
The game is, in my opinion, the hardest of all three AITD games. There are few enemies, comparing to the other AITD games, and most of them can and SHOULD be avoided, as they are unkillable. Sometimes the seemingly unkillable enemies must be defeated with a special tactic (using a specific item or weapon), so one must never say never.
Anyhow, while the graphics of this game seem hideous nowadays, back at 1992 they were state-of-the-art. This game is so fun and so creepy, even after all of these years, so simply try to overcome the graphics and enjoy this vintage Survival Horror.