Xenus 2: The New Nightmare
10 map replacement for Doom 2, obviously related to Xenus 1.5.
Construction: looks good but suffers horribly from Hyperdetailed Corridor Syndrome. That is if you strip away all the fancy detailing you end up with a series of small rooms and corridors. There is usually only one way to go at any given point. These maps are very linear. Needs more interesting map layout. The obvious exception is the town, map09; you can choose one of several buildings to go in first, there's height differences, it's much more open.
Texturing: uses some texture pack (supplied). The first few maps are very colourful. I mean, red, orange, yellow, green, and even purple versions of COMPBLUE and LITE3. It looks like an explosion in a paint factory sometimes.
Play: easy for the most part. You are overloaded with ammunition, especially shells, and the monsters are usually fairly light. However they are often in large quantity. Actually this is a good thing, lots of ammo, lots of monsters, especially monsters that die easily, I like that. Map07 is somehow noticably harder than the rest, due to extreme lack of health. It ends in an arena fight with two cyberdemons, I reached there with 2% health. I was... lucky. Map10 has a new boss monster that is absolutely trivial to kill in comparison.
Bugs: a few. Map05 is a bit confused over the purpose of the blue key, for example. You don't need the key and the area behind the door is blocked off by a sector whose tag doesn't correspond to any linedef. You can still finish the map though. I think maybe you were meant to get the key, go up there, and then that opens the teleporter to the final part of the map? Moving on, one of map06's secret sectors can be wiped by a floor transfer if you don't step onto it before it stops moving. Map09 has two locked doors too close together, so you can't open the second one because keypresses are eaten by the back of the first one. This is basically a ZDoomism.
Overall: pretty decent, but for the bugs. It's obscenely linear and easy on UV. Just follow your nose; even the 300-monster map06 doesn't take long to do. Map09 is probably the best one. It's worth playing, I think.
Deimos Anomaly Redux
Yet another ExM1 remake! This time, E2M1, but of course you'd know that from the title.
Quite detailed, and doesn't just blindly copy the original, there's a nice bit of skin'n'blood tunnelling in there too. However it is rather cramped. Gameplay is not trivial, there aren't many monsters* but there's relatively little health and ammunition either, so be careful. The blood is extremely toxic.
Pretty good, worth a play.
* Admittedly there should be more monsters in it than those I fought against. This map is a rare example of a ZDoom map that doesn't have any ZDoomisms. The map uses ZDoom features, but they degrade gracefully and you can play it in a Boom-compatible port. Basically it just adds a couple of new monster types, which just generate unknown thing warnings. I wish all ZDoom maps were this Boom-compliant.
A single map for Doom 2. It starts off as a detailed vaguely E1-style techbase, but degenerates into copy-paste heaven.
It's a one-monster map. There are something like 1500 troopers. However there's no health, armour or decent weapons either. If you can get that far, there is a shotgun and a chaingun, but I didn't before I inevitably died from a thousand cuts. Quite frustrating - I barely got out of the first room!
I cheated a bit to see the rest of the map; however, it was quite dull. Imagine two very long, winding grey corridors full of crushing ceilings. If you run all the way to the end where they meet up again there's a red brick area with a plasma gun. Picking this up releases the bulk of the monsters into the corridors, where most of them immediately get squashed. Two of the copypasted side chambers - 20 troopers each, and there are 56 of them - have incorrect sectors tagged, one doesn't open fully, the other doesn't open at all, so you can't get 100% kills.
Probably not worth the bother. Disclaimer: I really hate having to fight with the pistol, you might like it better if you don't.