The hidden faction within the Fort, "The Mausoleum", had devoted centuries to learn about the Fort.
They have managed to, under specific conditions, take physical parts of the fort out in the world while retaining its special properties.
One branch of the Mausoleum supporter in the outside world had seeked everlasting life. Yet safe, sustainable access to the conscious soul had always been a barrier.
30 years ago, Dr.J___ J____ W______, an outside consultant who never knew about The Mausoleum, wished to bring back his dead daughter in whatever form possible. He utilized Mausoleum knowledge and created the "Soul-Activation" technology. It would activate selected dormant Brainwave pattern released into the stratosphere after death, where it would accumulate into a residual energy pool that directly influence further human development. The Woken Soul would then existed as electric pulses sustained by the Soul Activation System, as a form of cyber-ghost that was from the will of the original dead.
After the "Ghost in the Stratosphere" incident, The Mausoleum took over the few remaining notes of the so-called "Soul-Activation" tech, the portion that mainly focused on activation of the "digital ghosts", and merged the special quality of The Fort's Dream into the theory in order to achieve the goal of true resurrection and everlasting life.
The "Silver Sarcophagus" The UNION used, was actually an extension of the Fort itself: If anyone managed to open up a "Silver Sarcophagus" without triggering the explosive failsafe AND without causing a BLACKOUT INCIDENT, they would only find a very basic computer system linked up to a small chunk of the Fort. There wasn't even a battery as it was completely self-powered. What little electricity it needed was only to power the computer screen on it, put on separate power source for the sake of subterfuge.
The reason of the UNION's completely randomized nature of doing things, were because they were running on the incomplete thesis of DR.W______'s tech powered by the literal realization of a chaotic dream. The "Agents" were dead souls given properties of a variation akin to High-Level Contaminated Fort Residents, and they existed in their pocket of little dreams cloistered from under the Fort's when they weren't inhabiting a body. All of the 50+1 bodies accessible, at least for the few with identities known to Mausoleum, were all Fort-Level Contaminants (#1,8,22,37,39. One of them was actually Mausoleum Inner Sanctum), and they were all probably alive deep in the Fort somewhere, with the UNION only having extremely weaken version of their physical copies to use. (The highly-specific usage of powers the Shells have, were probably from how they would use it if they were themselves. And their Maximal Overdrives *not listed in rules* were small snippets of their individual Final Contaminant Forms.)
The "melting away after almost 3 weeks" aspect of UNION agents, were almost exactly the same as those with high-level 舊寨成癮症 trying to leave the fort. Both of which were likely due to the Fort not able to maintain that dream outside of itself for an extended period, though UNION shells were able to alleviate it somewhat due to both Mausoleum processes and the Souls were not actually part of the Fort's Dream.
The Mausoleum was the mysterious backer who was mainly using the UNION as lab rats, even if the Archivists themselves thought they were doing good.
The Mausoleum itself had already developed their own "Gen-4" version of the technology for in-house use, more pinpointed and lenient in every way with a different set of 50s on another level. Their outside factions also rarely operate in the outside world, but there their fort-related resources would be extremely limited, as even lower-grade fort entities would only have an extremely small window to exist at reduced effectiveness.
But its a waste to not use a good rat.
(Come to think of it, while The UNION might seemed to be pseudo-scientific, underneath it all its actually wholly necromantic. A fact that none of its members knew. @3@ )
UNION ops were strictly forbidden to enter The Fort. Period.