There are 50 levels in all, and the mod is noted for its level design quality and, in contemporary circles, its coding.
This was Ragland's second mod for Wolfenstein, his first being 1998's Assassinate Hitler.
An SDL port was released on June 5, 2013. It was ported by MCS Amsterdam.
The following is directly from the Read Me file that came together with the mod:
Allied Intelligence has just uncovered the secret Nazi plan called Operation Eisenfaust. Put simply, it involves the creation of mutant soldiers from the bodies of the dead. The maniac behind this entire experiment is the crazy scientist Dr. Schabbs. As it stands, all of the mutants he has created are still located in his lab, and you must destroy him and his mutants before they can be released, assuring a certain Nazi victory. There is also rumor of one special mutant created by Schabbs, called the "Ubermutant". If you find him, he too must be terminated. Your time is limited, so hurry off to Castle Hollehammer...The storyline is loosely based on Episode 2, and uses a lot of elements from that particular episode, e.g. the high presence of mutant guards and Dr. Schabbs being the final boss.
Level guide Edit
In the Read Me file, there is also included a very detailed description of the different levels. Contemporary authors such as BJ Rowan and Barry Christian would come to use, or were already using, similar layouts.
Certain levels were notorious. Level 9 was a secret level (description below) and level 19 featured no music.
UNIT 1: The Old Castle (Levels 1-8)
This first section is fairly normal and is similar to original Wolf levels (but probably harder) These levels represent the Old Castle, which is the only part of Schabbs' massive lab visible from the outside. This is because the lab extends back into the mountain, behind and below the castle entrance. These levels have a moderate number of mutants, but a lot of regular guards also. At least for the early versions of this add-on, these are the only levels that have their own par times.
UNIT 2: The Reactor (Levels 10-19)
This is the section that probably needs the most explaining, and is the first to use a new key. First, the setting: The Reactor is the part of Schabbs' lab where all the energy is created to fuel the machinery and equipment to make mutants. Therefore, you are likely to see many nuclear drums and waste laying around. The first 9 levels of this unit require that you get the NUCLEAR KEY, sometimes in addition to the gold and silver one. This means that some levels require three keys to make it out. Level 19 gets even worse. This level is the CORE of the volatile reactor. There are very few guards, because the reactor is melting down and is going to close off forever. If you don't make it out in time, you'll melt in the explosion of nuclear ooze. You must navigate the maze as the reactor makes strange noises in the distance. If you do it correctly you'll come to a locked door (for which there is no key), with two nuclear ACHTUNG signs. Here you must wait for the one Nazi guard left in the reactor to come through the door. Shooting him in the doorway will leave it open for you, and you'll see the elevator off to the left. If you get there too late, and the guard has already left the area, you're toast. The guard USUALLY appears at the door about 2 minutes and 10 seconds after the level starts. HINT: To find the path to the exit, follow the "leaking nuclear barrels".
UNIT 3: The Bio-Labs (Levels 20-24)
After the chaos of the reactor, you must penetrate the gross and eerie bio-labs. This is the area where the mad doctor performs inhumane tests, looking for breakthroughs in the mutant technology. Mutants galore in this area, and plenty of dead bodies and skeletons too.
UNIT 4: Security Central (Levels 25-30)
Security Central is located about halfway into the mountain-top, and its main purpose is to defend the areas behind it. The Nazi leaders figured that any spies would be stopped at this point, if they weren't devoured by the reactor. There are no mutants on these floors, but PLENTY of other Nazis, as this is the most heavily guarded unit.
UNIT 5: The Factory (Levels 31-38)
The factory is where all the mutants are fitted with their cleavers and chest-guns, during an assembly line process. This unit, like the Reactor, requires the use of a third key. In this case, it is the Factory Passcard. The last two levels of the unit, don't really belong to the factory, but are sort of left-overs. Level 37, the Nazi Lodge, is a huge dorm for all the Nazi soldiers. Level 38, Creepy Caverns, is a tunnel-filled level which connects the factory to the castle, all the way across the mountain.
UNIT 6: The Castle (Levels 39-48)
The Castle is built within the remains of an ancient German castle, which rests at the very peak of the mountain. These ten levels are similar to the first castle unit, only slightly more difficult. The close you get to the end the more and more mutants you will see.
UNIT 7: The Boss Levels (Levels 49-50)
Not much to explain here. The Ubermutant is on level 49, Schabbs is on 50. Both are difficult, but certainly beatable.
You may have noticed that level 9 is missing above. That is because it is a secret level which is reached off of level 8. Its pretty well hidden and VERY bizarre, in addition to being difficult. Check it out at your own risk (you might not get back up to the original levels)
Schabbs 2000 was lauded upon release, and would continue to inspire and serve as template for many future mods, especially those centered on the classic Wolfenstein setup. Graphic changes in Schabbs 2000 were minimal, but certain wall patches used in later mods made their debut here (e.g. the checkered marble) and the base of the code would be discussed well into the 2000's, and would later be replaced by the next major step taken within coding for the Wolfenstein 3D engine, 2001's Spear Resurrection.
Level 9, as mentioned earlier, was a bonus level that featured a striped ceiling and a large level made jointly by Gary Ragland and Chris Chokan. This would later serve as inspiration for 2007's All This & Wolf 3D's level 69, and certain tricks from the level would be explored further in Chris Chokan's 2003 EXE patch, Weird33.