Registered Phenomena Code: 420

Object Class: Gamma-Red

Hazard Types: Aggression Hazard, Sapient Hazard, Transmutation Hazard, Emotional Hazard, Visual Hazard1

Containment Protocols: RPC-420 is currently contained within a specialized structure, hereby referred to as OL-Building-420. Such building contains a segment mechanically suspended over a 90m deep hole. OL-Building-420 is situated on Site-031-1’s outskirts by the Engineering Component in collaboration with the Protocol Laboratory:

Should RPC-420 escape its containment and go missing, MST Charlie-09 ("Countryside Hypocrites") is to track and recover the anomaly under any means necessary. They are authorized to conduct their operations in an area spanning Alabama, Louisiana, and the Northwest regions of Florida. Further incidents resulting from the containment breach may merit a distress call to the closest Protectorate’s Neutralization Team.

Any attempt of lethal force is strictly prohibited against RPC-420 due to the unpredictability of its anomalous properties, as are any other types of retaliation by excessive amounts of force (eg. rocket launchers, missiles, strategic bombardments). All offensive responses to RPC-420 are to be used solely for re-containment.


First recorded snapshot image of RPC-420 taken by dashcam footage.

Description: RPC-420 is the designation given to an organism that most accurately genetically resembles the Macrochelys temminckii.5 RPC-420's anomalous properties manifest in its method of guaranteeing survival. RPC-420 possesses the ability to engage in hyper-accelerated evolution, wherein RPC-420 rapidly mutates its cell structure to produce new, imminently-advantageous physiology in the face of a hazard. As a result of this anomalous ability, and based on the Authority's current knowledge of the anomaly, RPC-420 is conclusively capable of evading/extinguishing all hazards presented to it. However, the generation of this new physiology is permanent, and as such they do not only serve as a short-term solution to survival, but may in fact hinder RPC-420's ability to gain advantages in future hostile situations where they are not needed, or obstruct necessary mutations. This flaw serves as the basis of current containment protocols.

Furthermore, RPC-420 exhibits a Proxior-Motus6 class memetic effect wherein subjects experience overbearing apprehension and fear of RPC-420 upon direct viewing. Subjects claim that feelings of panic manifest as a result of RPC-420 exhibiting malicious intent towards the subject. This extends to group viewings, including those of more than 17 observers, who have each been recorded believing that RPC-420 was after them and them only. This memetic effect is permanently generated by RPC-420, even in cases where it is not aware of the observer's presence, and is ineffective towards individuals who have received any form of memetic inoculation.

It is largely agreed by the OAS’ Department of Biology that this memetic effect is RPC-420's first mutation, and exists for the purpose of deterring any creature that it would consider a threat. It is for this reason that RPC-420 was not required to make use of its physiological mutative ability for its entire life leading up to the events of its discovery.

Whether RPC-420 consciously generates these defense mechanisms, unconsciously does so, or is being influenced by an external unseen force is, at this time, unknown. RPC-420 seems to be capable of reacting to anything it perceives to be a threat to itself in a fraction of a second (See table below). Firearm tests make it uncertain whether it requires to be aware of the threats in question in order to react accordingly.

Since acquisition/containment, RPC-420 has evolved to possess the following physiological mutations:

Cause Mutation
75 mp/h ██████ brand semi-truck collision. Skin and carapace undergo change in cell-structure and visual appearance, appearing similar to volcanic rock. Generation of small obsidian shards from the carapace, all on the left side of the creature. Right side remains unchanged. According to on-board dashcam footage of the collision, RPC-420 appears to assume a physical density great enough such that the surrounding ground and asphalt cracks and sinks down under the anomaly's weight. RPC-420 absorbs impact and suffers no damage, save for the formation of fissures and fractures in the form of the aforementioned obsidian growths, many of which fall off of the carapace.
9mm round fired at RPC-420 from a Glock firearm. Spontaneous generation of organisms resembling cultivated Flammulina velutipes7 located on the coastal regions of the carapace, appearing to have the same dark-brown color and composition of RPC-420's carapace. Growths generate and mature to their full size of 0.6 meters in 0.0004193 (±0.0002) seconds, and are outstandingly effective at intercepting and absorbing damage from standard gunfire. When not under attack, they will assume plasticity and flexibility consistent with their non-anomalous, naturally-growing counterparts.

The following mutations were as a result of testing within a controlled environment on Site-031.

Exposure to a memetically-inculcated image meant to induce a temporary catatonic state in lifeforms. Electrical activity within the brain jumps by 400%. Readings indicate a comprehensive reconfiguration of neural networks, resulting in total inoculation. For a period of 1 week and 4 days following this mutation, RPC-420 loses the ability to send electrical impulses to and control its right eye and hind leg.
Exposure to 250 Pepsini8 Formation of 2 new appendages under carapace, manifesting as long, thin, 3-jointed "arms" terminating with a multi-pointed mallet head, all insectoid in appearance. Designated RPC-420-1. Appendages are capable of stretching out to 4 times the width of RPC-420, and work to quickly swat the 250 wasps. The power of each swing results in RPC-420 being erratically thrown around and disoriented. After all wasps are dispatched, left-side RPC-420-1 immediately goes limp and right-side RPC-420-1 freezes in place for a period of 5 seconds, then begins rapidly swinging at RPC-420's head.
Repeated bludgeoning to head from right-side RPC-420-1. The fractured bones in RPC-420's skull, resulting from repeated impacts, emerge through the dermis on the right side of RPC-420's head, and grow hook-like structures along their edges. RPC-420-1 collides with this structure and is subsequently unable to free itself, having been effectively subdued. RPC-420's right eye is completely obstructed by this point.
After a period of 3 hours, right-side RPC-420-1 physically severs from its base under the carapace, and ceases motions to attempt to dislodge itself. Occasional violent spasms were observed until nervous connections routed from RPC-420's brain, through the skull fragment mutation, and to the end of RPC-420-1's old base. From this point, RPC-420 is capable of fully controlling right-side RPC-420-1, using it to aid with locomotion, righting itself when it falls onto its back, and occasionally using it as a weapon.


RPC-420 Anomalous Contact Report




RPC-420 was discovered on 02/10/1988 following interception of a 911 call reporting a semi-truck collision with a "monster turtle from Hell." Local Containment Teams dispatched field agents to confirm the presence of anomalous contact and to secure RPC-420.

Following this call, a detachment of MST Charlie-09 ("Countryside Hypocrites") was dispatched to acquire RPC-420. At that point, it was uncertain whether the incident was a result of a physical anomaly or a cognitohazardous effect; the dashcam footage being too obtuse to identify if the caller's testimony was an accurate depiction of the events.

Addendum 420-234A:

Incident Report: TALON STRIKE

Anomalies Involved: UO-556,11 RPC-420 Objects supposed to have interacted during the incident.
Incident Type: Fixer-Upper Anomalous event destroyed part of OL-Building-420
Incident Location: Site-031-1 OL-Building-420
Cause of Incident: UO-556 N/A
Status: Resolved Further assessment pending


UO-556 entered geosynchronous orbit, and was quickly destroyed. Interaction with RPC-420 suspected.


00:40: UO-556 is sighted on the asteroid belt. It deploys its weapons array, destroying a number of asteroids. Kinetic and laser weapon systems are observed. AEDF vessels report that the object appears to ignore them; UO-556 is nevertheless deemed a hostile threat. TERFLT and INFLT are alerted.

14:00: UO-556 attaches itself to Asteroid 2019 OK, seemingly using it as cover between itself and nearby AEDF vessels/lunar installations. AEDFS Mars Vizier (Lilienthal-Class, INFLTNR) gives chase, with orders to attempt communication with UO-556 if possible, but destroy it if necessary.

14:34: Communication attempts are unsuccessful; the object is unable or unwilling to respond. UO-556 detaches from 2019 OK, and engages in geosynchronous orbit with Earth. Its weapon barrels are aimed toward the surface. Its firepower is expected to be capable of potentially penetrating the Earth's upper crust, and subsequently UO-556 is registered as posing an imminent threat to most life on Earth. Mars Vizier is ordered to engage.

15:10: Before Mars Vizier can engage UO-556, a minuscule unidentified object exits Earth's atmosphere, impacting the anomaly. UO-556 explodes outward, then collapses in on itself. The remains of UO-556 disappear into a single point.

15:12: Breach alarms sound at OL-Building-420. Massive damage to the ceiling caused by forceful exit is noted.

15:13: MST Yankee-01 is deployed to the location in order to survey damages and recontain RPC-420 if necessary. RPC-420 does not appear to have breached containment.


Personnel Injured:

  • N/A

Assets Compromised:

  • Ceiling of OL-Building-420


After the incident, RPC-420 was observed to be covered in an unidentified substance, briefly emitting high amounts of particle radiation before returning to normal. It is assumed that it quickly mutated to absorb or nullify the radiactivity, although the specifics of such a mutation are still under study.

Yankee-01 operatives have claimed that they saw RPC-420 gnawing on a spherical, glowing, quasi-incorporeal device covered in wires, which was confiscated with exceptional difficulty for further study.

Analysis of Incident TALON STRIKE:

I've spent a long time analyzing all of the data associated with our recent extraterrestrial fiasco. I believe it has a lot of implications for RPC-420, and its potential to be immensely dangerous.

I am mostly certain that RPC-420 was the small object spotted accelerating toward UO-556. The timing, the eyewitness reports, the recordings. It all points to 420. Personnel who were present in RPC-420's containment quarters claimed they were not looking directly at the containment chamber itself when the hole was ripped through the ceiling. When they did turn to look, as any conscious person would, they curiously noted that RPC-420 was still present in the chamber, covered in that radioactive substance.

Look, it's staring us right in the face and we're all too terrified to admit it, RPC-420:

  1. burst through our site's 9-meter-thick reinforced ceiling,
  2. accelerated into the atmosphere,
  3. penetrated UO-556 like toilet paper,
  4. and then returned to its containment chamber.

This occurred all in the span of time it took for our personnel to turn and look toward the sound. I believe RPC-420 had a vital component of the craft's energy system in its mouth when it returned, I suspect it's some kind of energy core. We've run tests trying to hook this thing up to an interface that can transfer its energy to human technology, and we've been getting mixed results. If you're really interested in the specifics contact me and I'll let you know when I finish the papers for the full study but simply put, RPC-420's act of ripping the core out from UO-556 caused it to trigger some sort of gravitational singularity that ate it whole. We don't know if it's still out there or if it's dissipated but we may have a large explosion in the sky if it does have yet to expire.

The point I'm trying to make here is that RPC-420 knew how to take out UO-556. We've been beating our heads against the (new) wall trying to figure out how exactly it figured it out, since its got the intelligence of a damn turtle. Nobody wants to be the first to suggest that RPC-420 and UO-556 are related in any capacity, it sounds ridiculous on its face. Here's some food for thought though: With some help from the A.I. systems I calculated the positioning and orientation of this extrasolar spacecraft, and it turns out that it had its main armament barrel pointed straight at OL-Building-420.

Did it know about 420? Did it create 420, and in vain was trying to clean it up once for all? Why would it go after the turtle anyway when it's not even in the same star system as this craft's origin?

Does it know something we don't?

Then it hit me.

RPC-420 is a creature capable of mutation in speeds the likes of which we've never seen before, or at least out of what they let me see. You throw anything at it and it will have a solution in faster than the blink of an eye. It's jaw-dropping. One of these days, that thing, that turtle, or whatever the hell it is —could be a frog for all I care— It's going to get smarter. And when it does get smarter, we're going to have a serious problem on our hands.

If it can do its evolution magic without thinking, just imagine what it could do if it did it with deliberation. With a goal. It would just get more and more intelligent, and become powerful beyond measure to the point that we won't be able to control it, all the while possessing the primitive urges of a hungry impulsive amphibian animal. So the craft made the effort to terminate RPC-420.

What we saw was the most unprecedented display of defense capability we've ever witnessed from RPC-420. If anything I'm saying is in the ballpark of the truth, it will only get worse.

For the love of God, don't let RPC-420 near a book.

- Head Researcher Thomas Caldman, Protocol Team RPC-420


« RPC-419 | RPC-420 | RPC-421 »

Unless otherwise stated, the content of this page is licensed under Creative Commons Attribution-ShareAlike 3.0 License