Very cool mod that does exactly (for the most part) what it sets out to do. If you like the more horror/oppressive side of Doom (or even the palette of the original Diablo), this is your pick. It looks particularly good in Software mode with the diminishing lighting not shifting the reds (as much), and the lighter blues look absolutely *gorgeous* in particular with the Plasma Rifle.
This is a bit of an interesting one to revisit for me: Whispers of Satan was a mapset I played fairly early in my mapping career and it's influenced my approach to level construction and visual design more than I initially realized. At the time I ran out of steam around MAP22, but recently I decided to take another stab at it and finish all the levels. Which I did! Having done so, these are my thoughts.
Gotta start with the big one: Whispers of Satan is a damn good-looking mapset. Excellent texture usage and attention to detail were big draws for me when I first played this years ago and I ended up mimicking it a lot in my own work: to some degree I still do, honestly. Maps like MAP10, MAP16 and MAP28 stand out as particularly good examples of this school of design, with all the detailing work coming together to craft an excellent sense of place. This is bolstered by the custom soundtrack, which has some absolute bangers in it (in my decidedly unmusical opinion :P).
I also gotta shout out the fact that Paul and Kristian undeniably had fun putting this together, as can be evidenced by the silly little easter eggs and gags that are present throughout. There's the secret and super secret maps of course, but you can also spot a little bit of silliness in the main lineup and it's a touch I appreciate in the way that it gives a mapset life and charm. Again, it's something I was inspired by in my early mapping career and you can thank WoS for any gaff or joke you find in my own maps.
There is however an elephant in the room that I have to address and that is the map design itself. Other reviewers have pointed out the excessive symmetry that plagues a lot of the map architecture, but there is also a general sense of formula that can wear on you as you progress through the megawad: by the time you're in the final third of the main block of maps, you can distinctly see them falling into the same gameplay pattern and it starts chafing in a big way. MAP25 and MAP29 are two big culprits in my eyes, but there are plenty of early maps that follow the same formula and get a pass simply because of their placement in the megawad and (relatedly) the length of those experiences. This formulaic approach also creeps into the gameplay and monster usage and serves to make the latter half of the megawad something of a slog to get through, which explains why I didn't progress past MAP22 all those years ago.
I ain't gonna say that it doesn't deserve its Cacoward or anything though: I can appreciate the work that went into creating Whispers of Satan and the influence it had on what came after. It definitely has its flaws and as a gameplay experience it doesn't really hold up, but I can still admire it as a piece of Dooming history and I wouldn't be the mapper I am today if it didn't exist.
A 10-minute long map with fairly unremarkable gameplay. As is the case with many old maps, its main strength is the visual variety of the different locations. Still, there's not that much in terms of exploration or branching paths; a good part of the map is just going from room to room and shooting at the anemic groups of monsters. Not terrible, but not a classic.