Heretic: Shadow of the Serpent Riders (heretic.wad 1996)
I posted overall impressions in
that thread a few days ago but I thought people who check this one might be interested in a more detailed analysis of each episode.
As with Doom, I think the original shareware E1 is the best balanced and most memorable, despite being more limited in weapons and bestiary. Every level is unique and oozes personality, every encounter feels exquisitely balanced (though the episode is easy even on Smite-Meister), and every detail adds to overall atmosphere. I don't think Heretic's E1 is as good as Doom's E1 but it's still pretty great to play. Some secrets are well hidden but none feel unfair, and you never feel stuck when along the critical path even if the next step is not immediately obvious. The pace is really good and despite having played this one the most I enjoyed it just as much. The first level is such a good starter, and I think my favourite is E1M6 (The Cathedral). The final fight is also pretty cool, as defeating multiple Iron Liches when you don't have the Phoenix Rod actually takes some creativity (and judicious use of Tome of Power).
E2 introduces all the other weapons and all monsters except the Ophidian. This is where the monster count starts getting pretty high (Heretic is much more slaughtery than Doom IMO). The levels are still quite distinctive and I found a lot of them quite memorable, from running along the River of Fire (E2M3), to compensating for slipping on ice in Ice Grotto (E2M4), to climbing the titular Glacier in the secret level (E2M9). The boss level is also laid out pretty neatly. I don't think I ever realized this when playing under DOS, but the Firemace doesn't just appear like the other weapons; it only has a chance to spawn on a particular level, and its location is randomized when it does. The latter is fun, but the former I found annoying, as it's entirely possible to get unlucky and repeatedly have it not spawn, as happened to me this time, even while you have tons of ammo for it.
I think E3 is the weakest of the base episodes. The Ophidian is a fun monster (it fires a streak of fireballs, and one last one with a bit of a delay; you got to adjust your strafing pattern when fighting many at once) but the level design feels more forgettable. The final fight against D'Sparil was also a bit meh - it's not very hard, and his attacks are very easy to dodge, but he has a huge health pool and it just feels a bit boring and drawn out. There are small details where Heretic also feels a bit less lively than Doom - I kept wondering why the intermission maps felt so much more drab than Doom's until I realized they lack the small animations of Doom's - it's amazing how tiny details sometimes do make a difference. Overall though even E3 is quite consistent in quality even if isn't stellar.
The two episodes added by the
Shadow of the Serpent Riders patch are much more uneven. I remember them being hard (much harder than Doom's E4 was compared to the base episodes) but I forgot how obnoxious they could be. E4M1 is an awful starter level, with extremely tight ammo and none of the more powerful weapons, and to top it off it throws hordes of Ophidians and Saberclaws at you in small spaces with nowhere to strafe behind. When I ran into the Maulotaur I thought fine, at least it's possible to run around him and avoid fighting him head on. Then when I got to the level exit and found five Iron Liches standing in the way I threw the towel. E4M2 is not much better, but things do improve afterwards, as you get the more powerful weapons and start building enough ammo reserves to deal with anything (though this is also where monster counts start getting to 200). E4M3 (Ambulatory) and E4M5 (Great Stair) both have fun gimmicks. E4M9 (the secret level) is awful though; instead of using keys, it's an extremely linear switch hunt, and every time you flip one it opens what used to look like a normal wall somewhere on the level, with no indication whatsoever where to look. So you spend most of your time running around and backtracking to find which wall is now a passage. People give Hexen shit for its switch-hunts but that game was quite clear about where to go back to. At least the boss level is pretty cool, as you reconstruct the Shattered Bridge.
E5 is better in some ways, worse in others. E5M1 is absolutely manic but much better balanced than E4M1 thanks to giving you actual ammo to deal with what it throws at you. I think it's the most no-bullshit challenging map and as a result also one of the most fun. Most levels do turn into slaughterfests (most exceed 200 monsters), and I'm generally not a fan of this in Doom, preferring the killing to be balanced with exploration. Unfortunately E5 sins both ways; it takes the switch-hunts from E4M9 and makes them even worse, including linedefs that when crossed silently open something somewhere on the level - every time you hit a dead end, you go back and look all over the level again. Alternating massive slaughters with 10-minute bouts of running around is not my idea of balanced. It's a shame too because some of the levels look really cool - the Rapids of E5M2, the Quay of E5M3, the Colonnades of E5M6 and the citadel of E5M7. E5M8 pits you against eight (!!) Maulotaurs and is the most fun boss level in the game.
There's a hidden mini-E6 of sorts, and two of the levels are quite good. E6M1 is actually patterned after Raven's offices but is quite fun. feels a bit like an easier E5M1 where you come face to face with tough opposition but can manage by judicious use of your weapons and powerups. E6M2 is quite fun. E6M3 is actually one of American McGee's Deathmatch maps for Doom converted to Heretic, and doesn't even have an exit switch, so the minisode kinda ends there.
Ultimately I have mixed feelings about the game. E1 is very good, E2-E3 are good. But E4 and E5 are harder to recommend. Although they have some of the best challenges in the game, they also have some real bullshit, whereas in terms of difficulty or of puzzle design. I think both Doom and Hexen are better games, but it's still one of the seminal games of the golden FPS era.