Quake was a hit when it was released back in 1996. Heck, Shacknews even started as a fan site for it. So it's not surprising that players are still interested in the game and make mods for it. Case in point: The Forgotten Sepulcher, homage to e1m3 gone horribly wrong (or right, depending on your perspective).
Created by Simon "Sock" O'Callaghan and Henrik "Giftmacher" Oresten, the mod uses the original Necropolis map as inspiration, but takes it to a new level in terms of size, monsters and secrets. Whereas Necropolis had 65 monsters and three secrets, The Forgotten Sepulcher has several hundred monsters and 50 secrets. O'Callaghan even created Quakespike and Quakespasm engines just for this map.
"The map was originally planned to be a remix of the quake map e1m3, however as the map was so heavily rebuilt and restructured we simply passed a point where the 'e1m3 feel of the map' faded away," Oresten said in the mod's readme file. "Still, there are key elements and remnants of e1m3 to be found."
The allure of Quake was its fast pace and multitude of monsters. You rarely ever saw large maps because the pace would slow down too much. Watching the video that the duo put together showing off the map, you can see that there is hardly a second that goes by without dodging enemies or avoiding damage. There are plenty of ammo and weapon stashes as well.
"The map is very much focused around the introduction of unique monsters like the boil, swampling and boglords. Often the hardest part of designing new monsters is finding good ways to use them without making everything so scripted and rigid. Luckily the new monsters grew with the map and it felt like a journey of design for how they were used," O'Callaghan said.