Wow! What an amazing game! I've never played it before or back in the day so this was a first impression. It's such a huge 20 chapter adventure of FPS, scares, puzzles, cutscene movies and story, that you get so engaged in it, it really feels like you are controlling a character in a movie.
The graphics are impressive for the time, the mapping especially is so well thought out and designed that I was always amazed whenever I arrived at a new location. It's not all hallways and darkness, there's such a variety of fantasy like locations that it never gets dull.
The puzzle solving is done just right, from simple switches and keys to brain teasers and physical mazes, it's nicely mixed with the action and story throughout the chapters. I didn't find the puzzles to be overly complex, just enough to give you a good hard think.
The music being midi was ok but feels a bit underwhelming for such a movie like game, a CD soundtrack would of really enhanced the experience like what games consoles of the time would have back then, but it's still nice and eerie.
The inventory system is interesting, split into different categories where you can examine your items and read parchments to engage you more into the plot. It does take a bit of getting used to, between using an object with the environment, on yourself, or just holding it and finding out you've accidently switched it with something else.
The controls take some adapting to, following a guide to remap them to WASD is highly recommended, then it's a matter of how to shoot. Since the mouse is not locked to the screen, this gives you a bit of freedom. The gun will follow your mouse arrow around, so with enough practice you can take out enemies from different sides of the screen without moving an inch.
Speaking of enemies, they are pretty ugly and creepy, often spawning out of nowhere which can give you some scares. I recommend not leaving any alive else you will probably bump into them later on.
A good variety of weapons are to be found, guns, swords, wands and more, all having a unique look to them, and at times saving you ammo since some self recharge, very happy with those.
I found the difficulty to be very fair, if you have a good handle on the controls and don't mind a bit of puzzle solving, you can progress at a good pace.
Overall the story that this tells is done so well, with plenty of characters, good and evil, plot twists and mystery unravelling along the way. I couldn't wait to find out what happens next, where I was going to travel to or the puzzles I was going to solve. They really don't make games like this anymore, highly recommended!