FWIW I think the Rise of the Triad remake/sequel is going to do its best to fulfill these wishes of an old school FPS.

Ah but just like isometric RPGs and first person sneakers, one simply cannot have too many old-school FPSes, can they? :>

The more the merrier.

Frankly I had the same idea recently (and even prototyped such a game). I've also given some thought to the same things you mentioned and actually believe that a game in the style of the Doom era shooters would have serious potential for commercial success. The tough stuff would obviously be developing an attractive IP and truly addictive gameplay that not only mimics the classic gameplay but actually improves it. But yeah, I think that these days such a game could get some extremely positive reception.

Edit: However, a friend of mine showed me such a game earlier this year. I don't remember if it was using the Doom engine or one of its own, but it barely got any recognition, apparently. I don't know if it's because the developers just didn't try at all to advertise their game or whether it actually sucked. I'd have to ask him what the game's title was.

Thank you for all your suggestions. There seem to be a consensus as to what people expect from that type of game. Taking all this advice into consideration I revised my concept as follows:

- The game engine will use OpenGL in full RGB and real 3D instead of raycasting in software.
- Maps will probabbly use format compatible with GTKRadiant (open source Quake level editor) - this will allow mappers to design levels on par with those found in Quake 1-3 (no silly raycasting limitations).
- Two input modes will be supported: oldschool (X-axis only, no mouse) and newschool (mouselook with modern controls).
- The engine will support some modern features like point lights and dynamic shadows.

At the same time this is what's going to keep the looks oldschool:

- Low resolution: 320x240 or 640x480 VGA framebuffer (upscaling to native resolution will be done by the engine to ensure good image quality on todays displays)
- Textures will still be limited to 256 color palette with no filtering
- 2D sprites used for enemies and objects

Gameplay-wise I want to "steal" some ideas from Alien Breed: Tower Assault because I think it's a great game:

- Lots of kickass weapons like lasers bouncing off the walls.
- You will earn credits for buying weapons and ammo in special terminals - this will add some tactics (shall I buy a weapon now or save for something even better later?)
- Progression from level to level will be non-linear: frequent several exits, dozens of routes from start to finish the game/episode.
- Sector system: civilian, science, military etc. Path to finish will be shorter but more dangerous through military sectors while civilian sectors will be easier but the path leading through them will be longer and more complicated. This will also add tactical elements: while progressing in the military sector one could fallback into a civilian sector when low on health etc.
- Occasional red alert/autodestruction speedruns to exit
- Outdoor levels from top-down 2D perspective when traveling between buildings (to add variety).
- Possible 2 player co-op.

Let me know what you think!

This is problematic IMO. It feels like an artificial limitation of the player's ability to blow up stuff, which is key in a game like this. It also encourages hoarder's mentality, to try and scrounge every corner for the last penny. Players may not find this fun, but they'll be compelled nonetheless to try and do it.

Everything else sounds good. I like the bouncing lasers idea. That can even be used as a trap.

Well, one of the problems with old school shooters like Doom was that there was never enough ammo for some weapons and way too much for others. I remember playing through Doom and pretty much just using shotgun and chainsaw for nearly the entire game.

A system like that could potentially be used to balance that. Powerful weapons should be harder to keep fed, but they shouldn't be so difficult that you never bother to use them for fear of not having ammo when you need it.

Maybe multiple currencies then? One for buying new weapons/abilities, one for buying ammo/weapon upgrades.

I hate with a vengeance everything which is timed in a game. My fingers are big and slow, my brain is slow. I am never fast enough to actually press the keys. It ruined Grimmrock for me, I solved the puzzles, but never managed to do them in time (I am stuck on level 5 and deleted the game in pure frustration).... I like to take my time and be careful, sneak around and take mobs one by one with as little stress and hassle as possible. For the few of us that are not very good at anything timed, this can be bad.

That's one possiblity. Personally, I would rather have a certain number of credits available for converting ammunition. And let the weapons just be hidden like they were in the older games. I remember it being quite fun trying to figure out where various weapons were hidden in Doom.

I thought about it. Speedruns will probably be disabled at Easy difficulty level to accommodate people like you.

But it's all details anyway at this time... I'm still trying to decide if I want to go through with this plan. I'm going to start implementing a minimal engine in the following weeks just to get more accurate estimates on what's to come.

Thanks for all the feedback and keep it flowing! I want to hear more from you. So far you guys are convincing me that it's indeed a good idea. :)

another shooter is always a good idea.

Anyway, regarding easy settings - I am slow, but I do like a good fight. If you are considering having to play on easy to remove timed sequences, then it may a wise thing to be able to change difficulty in game so it is possible to still have hard battles but skip the timed parts? difficult, maybe. (one thing L.A. Noir did right was the freedom to play as you wanted)

If you must have a speed run, methinks there should be shortcuts that are accessible by grenade jumping and trick jumping, depending on the layout. But that's just me :P

You know, there's lots of game mechanics I don't like and if such things are present in a game then I usually don't blame the developers, I just accept the fact that this game is not meant for me. I usually liked dramatic sequences with a time limit but these are rarely present in games anymore because of the stupid tendency that devs are trying to satisfy everyone. So far it seems that MasterM is aiming at a certain niche that you don't belong to so it would be wrong to harm his vision only to make the game slightly more attractive to players who won't find it very enjoyable either way.