This is a "bricks 'n' metal" style WAD, to quote the TXT file. It comes with 3 WADs: DARKEN.WAD is the single player/co-op episode, there is a deathmatch WAD included too, and RESOURCE.WAD includes the new graphics shared by the two. There is also a dehacked patch included which alters the level names on the AUTOMAP, and the between-level texts, but you don't need it.
The episode clearly draws a lot of ideas from Doom, Doom ][, and Quake. Some of the textures imported are old Doom 1 textures, while others are more similar to textures from Quake. The new textures are good, looking similar but subtly different from the Doom ][ textures. There are also a number of Quake-like textures, like the red arrows to point the way, and those flat metal textures with red lights at the corners for teleports (slipgates or something in Quake).
MAP01 is a nice short starting level, with good architecture and lots of good secrets. There is some good use of decoration and the new textures. My only complaint is that there are too many secrets for such a short level.
MAP02 is a very Quake-like level, with lots of those metal supporting beams. There are lots of good traps and secrets at this level. The level progression is particularly good, since you see everywhere you need to go before you need to go there (e.g keycard, teleports in view but not accessible).
MAP03 is very similar to the Inmost Dens (original MAP14) in style, with lots of windows and a light brown stone architecture. You gradually work your way around the central yard collecting keys; the level progression is again good. The fights aren't as good at this level, since there are some awkward narrow passages which make it difficult to dodge properly.
While this level is good, it shows up what I see as one weakness of this WAD (perhaps the only weakness). The levels make the mistake of being too like Quake. One of the 2 reasons I didn't like Quake as much as Doom (the other was it was far too slow on my 486, but this WAD was fast) is that it was too brown. Doom levels are usually much more colourful and varied than Quake levels, but this episode is rather brown. This isn't a huge complaint, 'only as good as Quake' is still pretty good, and not all the levels in this episode suffer from this; but I think that given how good the architecture is, the authors could have done better than Quake with the textures.
MAP04 is a fairly large, detailed level, again in the rusty-brown Quake style. There are some very good fights at this level, especially the final fight (a load of skulls, chaingunners, and a pain elemental; you have to get them fighting each other to survive; I thought I had had it when I fumbled into the beserk pack!). There are again some good traps and secrets. There is a spiderdemon, but he is outside the building, so you can super-shotgun him easily enough from inside.
MAP05 is a very good level, similar in style to The Abandoned Mines (original MAP26). The level is very stylish, with lots of Quake style metal beams, mixed with Doom ][ style acid lakes look in upon by windows. This level has some very nice complicated architecture, which makes the play even more interesting.
MAP06 is a clever level, designed to be like a mine. There is lots of very good use of Doom ][ monsters to make it tricky to play. I particularly liked the release of an Archville into the mine tunnels which the player had already visited (and populated with dead monsters to revive!). The mine itself is dark, but not too dark, though perhaps a trifle small.
All the levels have new music; some I recognise from Requiem, others sound more like Heretic. Anyway, most of them are good, and several add atmosphere to their levels.
MAP07 is similar to MAP03, with lots of light-brown stone textures. This level is not as good as the others before it, it is lacking in detail in places. It still has some good architecture though. The fights are not as good either; the level tries to be "Dead Simple ][", but doesn't have the intensity of the original. You end up covering behind the small doors, popping out to fire one super-shotgun blast at a time into the mancubi. There is plenty of room for improvement at this level.
MAP08 is another rusty-metal level, similar to The Crusher (original MAP06). It makes excellent use of lighting effects and the new textures to give a very atmospheric level; perhaps the best use of lighting I have seen in any WAD. There are plenty of good fights and secrets.
There are lots of computer panels throughout the level (old Doom 1 graphics imported) which are used as switches; I think that this should have been mentioned in the accompanying TXT really. I got the idea immediately, because I use this sort of thing in my own WADs; someone else might get frustrated searching for a switch. Still, I've warned you now, so there is no problem!
Well, that's as far as I have played, but I can tell you I'm looking forward to playing on! This is an excellent episode, which keeps well to the "bricks 'n' metal" style, and makes very good use of new textures to give a distinctive feel.
One thing is for sure, I'll never play Quake again. This episode is very Quake like, and notwithstanding a couple of levels this episode beats shareware Quake hands-down. I look forward to the next release; a Quake 2 killer perhaps :-) ?