I am strongly considering running an old school (read: dungeon dive) game online for my real-life gaming group.  For several reasons we don't need wilderness or an intricate plot--everyone is buying into the premise that there is a dungeon, go explore it my dudes.  We have played a host of games, but I think an old school game checks a number of different boxes for a weekly 2-3 hour session on twitch/skype every week.  I would run basic D&D, but the problem is all the players know the modules or would know of them, so I need a newer adventure that will slip under their radar.  I own some of the core system products (e.g., ACK, Astonishing Swordsmen, etc.), but not many modules beyond my old D&D basic and AD&D "library."  So my ask is for a recommendation:

1. System: What system is the closest (including the same) to basic D&D with all its glorious tracking of encumbrance, illumination, turns/rounds, etc., but I'm open to a system with modest changes that include any sound, simple streamlining;
2. System/Module: Both system and module support a troupe style game that will forgive a player for missing a session (e.g., a nearby town that the group can return to with regularity and trade out characters if the fighter is missing that night); and
3. Module: Medium deadly with cool traps, challenges, foes and . . . you know, the stuff of legend.  I'm not an over-the-top crazy gonzo guy, but clearly "because Magic" is always a valid answer.

Thanks in advance.

Quote from: Ted;1053035I am strongly considering running an old school (read: dungeon dive) game online for my real-life gaming group.  For several reasons we don't need wilderness or an intricate plot--everyone is buying into the premise that there is a dungeon, go explore it my dudes.  We have played a host of games, but I think an old school game checks a number of different boxes for a weekly 2-3 hour session on twitch/skype every week.  I would run basic D&D, but the problem is all the players know the modules or would know of them, so I need a newer adventure that will slip under their radar.  I own some of the core system products (e.g., ACK, Astonishing Swordsmen, etc.), but not many modules beyond my old D&D basic and AD&D "library."  So my ask is for a recommendation:

1. System: What system is the closest (including the same) to basic D&D with all its glorious tracking of encumbrance, illumination, turns/rounds, etc., but I'm open to a system with modest changes that include any sound, simple streamlining;
2. System/Module: Both system and module support a troupe style game that will forgive a player for missing a session (e.g., a nearby town that the group can return to with regularity and trade out characters if the fighter is missing that night); and
3. Module: Medium deadly with cool traps, challenges, foes and . . . you know, the stuff of legend.  I'm not an over-the-top crazy gonzo guy, but clearly "because Magic" is always a valid answer.

Thanks in advance.

ACKS + The Sinister Stone of Sakkara will serve you in good stead. The Sinister Stone of Sakkara is inspired by Keep on the Borderlands and offers a starting base (a Roman-style fortress), a small wilderness, and a medium-sized dungeon sandbox. The top level has rival factions of kobolds, goblins, hobgoblins, and orcs, while the bottom level has more sinister chaotic aberrations and a legendary magic item. There's all the things you want from a classic D&D-style module - swarms of humanoids, a young dragon, chaotic cultists, weird ooze monsters, random charts of abominable mutations, etc. The module includes suggestions for further play around the fort afterwards. (I'm the co-designer so please note this is a biased recommendation!)

Quote from: amacris;1053043(I'm the co-designer so please note this is a biased recommendation!)

Biased recommendations are best because they are transparent and honest.  Thanks.  I already have ACKS, so picking up Sinister Stone shouldn't be too hard.

Run DCC, it has a ton of top notch modern adventure modules that are very old-school in style.

BX D&D and Keep on the Borderlands then Isle of Dread. All three are up as PDFs on DriveThru as of last check.

Quote from: Ted;1053035I am strongly considering running an old school (read: dungeon dive) game online for my real-life gaming group.  For several reasons we don't need wilderness or an intricate plot--everyone is buying into the premise that there is a dungeon, go explore it my dudes.  We have played a host of games, but I think an old school game checks a number of different boxes for a weekly 2-3 hour session on twitch/skype every week.  I would run basic D&D, but the problem is all the players know the modules or would know of them, so I need a newer adventure that will slip under their radar.  I own some of the core system products (e.g., ACK, Astonishing Swordsmen, etc.), but not many modules beyond my old D&D basic and AD&D "library."  So my ask is for a recommendation:

1. System: What system is the closest (including the same) to basic D&D with all its glorious tracking of encumbrance, illumination, turns/rounds, etc., but I'm open to a system with modest changes that include any sound, simple streamlining;
2. System/Module: Both system and module support a troupe style game that will forgive a player for missing a session (e.g., a nearby town that the group can return to with regularity and trade out characters if the fighter is missing that night); and
3. Module: Medium deadly with cool traps, challenges, foes and . . . you know, the stuff of legend.  I'm not an over-the-top crazy gonzo guy, but clearly "because Magic" is always a valid answer.

Thanks in advance.

Since you have a number of things that are essentially built upon the same core game, you can run the game under Moldvay/Cook D&D, while using elements from others.  So, replace some of the stock standard monsters, and use some of the interesting tables for various encounter elements, etcetera.  

How about Moldvay/Cook, with B4 The Lost City, which you might already have.  Switch out some of the monsters and tables in the module or rule booklets with those in a later similar game, Astonishing Swordsmen & Sorcerers or Adventurer, Conqueror, King, which you own.  If I was doing it, I would switch most of the magic treasure items, since I find TSR (or Wizards) modules to have sort of so-so magic treasure, generic. There is also an interesting compiled sourcebook over at Dragonsfoot for The Lost City that has all sorts of good ideas from DMs that have enjoyed the module over the years, helping to add even more to your campaign.  

One caveat for this suggestion is to keep the changes behind the ref screen, don't make changes to the game the players will need to know, if you want to have an authentic game that players are anticipating, not a bait switch on them. You know, don't say your going to play Moldvay/Cook, but turn it into 2nd-5th, with a bunch kits, feats, skills or something.
The Lost City Sourcebook at Dragonsfoot

Quote from: Omega;1053060BX D&D and Keep on the Borderlands then Isle of Dread. All three are up as PDFs on DriveThru as of last check.

The OP said "all the players know the modules or would know of them, so I need a newer adventure that will slip under their radar" so the great classics of the canon are off the table.

"Kthenta's Dark Repose" is a mini-adventure in Pegasus Magazine from Judges Guild (circa 1982). The link below is for the whole magazine which includes a couple different dungeons.
https://www.drivethrurpg.com/product/57913/Pegasus-Magazine-VII-AprMay-1982?term=pegasus+vii&manufacturers_id=31

It's one of my favorites to run, its Old School Cred is impeccable and even the hardcore AD&Ders never heard of it.  

As for system, there are a dozen OSR free systems. My favorite is Swords & Wizardry: White Box.

However...if you are looking for a mini-campaign of multiple delves instead of a single dungeon, I highly recommend The Black Ring from Pegasus Issue 1.
https://www.drivethrurpg.com/product/56279/Pegasus-Magazine-I-AprMay-1981?manufacturers_id=31

Like  Spinachcat mentions, the off the beaten track adventures from the late 70s and early 80s that were often pretty difficult to actually find then are readily available today electronically.  The Black Ring in the Pegasus issue was written by Dan Hauffe. He wrote The Illhiedrin Book for Judges Guild, which I think is one of the better early low level adventures, with some tricky bits to it.  You could even combine the two!  Shoot, something I would like to do.

Labyrinth Lord's deep underground adventures would work well with Adventurer, Conqueror, King, such as Barrowmaze.

The art free version of Lamentations of the Flame Princess is available for free too, if you are starting the search for free D&D based games.  There are a ton out there.  Lots of creative people adjusting the concept around different ways.

System - I like Swords & Wizardry best, I like using ascending AC & to-hit-bonus and I very much like the single saving throw, which is very flexible and can be used for various event resolution checks, plus I don't need to look up a saving throw table to use it.

Adventure - I'm loving Stonehell Dungeon (from Lulu), I've run dozens of sessions over the past year or so and it feels like barely scratched the surface of its potential. The presentation is brilliant, incredibly easy to run with minimal prep. Definitely recommend. A decent smaller & free alternative is Dyson's Delve - https://rpgcharacters.wordpress.com/maps/dysons-delve/ - treasure on the upper levels needs toning down (a hobgoblin with 500gp) but overall very nice.

In both cases the PCs will need a home base, eg Morgansfort from Morgansfort & Beyond at basicfantasy.org, which also has tons of free (or print-at-cost) adventures.

Quote from: Spinachcat;1053090However...if you are looking for a mini-campaign of multiple delves instead of a single dungeon, I highly recommend The Black Ring from Pegasus Issue 1.
https://www.drivethrurpg.com/product/56279/Pegasus-Magazine-I-AprMay-1981?manufacturers_id=31

Isn't The Black Ring for levels 10-15, something like that?

The Ilhiedrin Book is good, and suitable for starting PCs. Many of the old JG adventures suffer from poor presentation though IMO.

Oh, the Judges Guild stuff is printed on left over newsprint from the 50s. The layout of Illhiedrin is good for Judges Guild, though. hmm...Looking over the Black Ring, it is for 10-15 all right.  So, that one probably isn't going to work  Spinachcat.  It brought to mind Illhiedrin, though.  

Stonehell Dungeon is a good suggestion S'mon.  Cool big dungeon choice.

Judges Guild is where a lot might go to find old less known adventures, but the RoleAids adventures are usually even less known by those that contribute to forums and such online, which has always seemed odd to me.  Many of the RoleAids adventures from Mayfair are quite good, though I don't care for the Fez series or Final Challenge.

Quote from: Kuroth;1053081Since you have a number of things that are essentially built upon the same core game, you can run the game under Moldvay/Cook D&D, while using elements from others.  So, replace some of the stock standard monsters, and use some of the interesting tables for various encounter elements, etcetera.  

How about Moldvay/Cook, with B4 The Lost City, which you might already have.  Switch out some of the monsters and tables in the module or rule booklets with those in a later similar game, Astonishing Swordsmen & Sorcerers or Adventurer, Conqueror, King, which you own.  If I was doing it, I would switch most of the magic treasure items, since I find TSR (or Wizards) modules to have sort of so-so magic treasure, generic. There is also an interesting compiled sourcebook over at Dragonsfoot for The Lost City that has all sorts of good ideas from DMs that have enjoyed the module over the years, helping to add even more to your campaign.  

One caveat for this suggestion is to keep the changes behind the ref screen, don't make changes to the game the players will need to know, if you want to have an authentic game that players are anticipating, not a bait switch on them. You know, don't say your going to play Moldvay/Cook, but turn it into 2nd-5th, with a bunch kits, feats, skills or something.
The Lost City Sourcebook at Dragonsfoot

Thanks, I always loved the Lost City (i.e., my character was an entirely unique dwarf by the name of Thoren Oakenshield--no relation of course, I mean the first name is spelled differently.  Ah to be 9 year old again); but I am concerned my players will know that adventure even if I reskin it substantially due to its iconic nature. Plus I would like to learn a new dungeon myself, but thanks for the suggestion it does give me food for thought.

Quote from: amacris;1053083The OP said "all the players know the modules or would know of them, so I need a newer adventure that will slip under their radar" so the great classics of the canon are off the table.

Sadly, yes I am looking for something no one knows, a Search for the Unknown if you will.  Sorry, had to do it.

Quote from: Spinachcat;1053090"Kthenta's Dark Repose" is a mini-adventure in Pegasus Magazine from Judges Guild (circa 1982). The link below is for the whole magazine which includes a couple different dungeons.
https://www.drivethrurpg.com/product/57913/Pegasus-Magazine-VII-AprMay-1982?term=pegasus+vii&manufacturers_id=31

It's one of my favorites to run, its Old School Cred is impeccable and even the hardcore AD&Ders never heard of it.  

As for system, there are a dozen OSR free systems. My favorite is Swords & Wizardry: White Box.

However...if you are looking for a mini-campaign of multiple delves instead of a single dungeon, I highly recommend The Black Ring from Pegasus Issue 1.
https://www.drivethrurpg.com/product/56279/Pegasus-Magazine-I-AprMay-1981?manufacturers_id=31

Thanks, this is intriguing for another reason; we all played the Dark Tower https://en.wikipedia.org/wiki/Dark_Tower_(module) at GenCon this year and I think it was a hit.  Our GM used Amazing Swordsmen et. al. of Hyperborae.  I will definitely look into it.