— Exploration Log 02/12/20██ —
Situational Report: Special Task Force Epsilon-55's ("Devil May Care') Alpha Squad was deployed to explore the contents of SCP-30000, due to their expertise in theological anomalies. They were ordered to catalogue and, if possible, retrieve any anomalies they come across. If an instance of SCP-30000-A manifests, Alpha Squad was to wait for Beta Squad before continuing into the anomaly.
<Begin Log - 3:23:46 GMT>
E-01: Attendance.
ALPHA-1: Kali, here.
ALPHA-4: Link, here.
ALPHA-2: Romeo, here.
ALPHA-5: Mona Lisa, here.
ALPHA-3: Rain, here.
MEDIC-1: Nightingale, here.
E-01: Excellent. Proceed.
Alpha Squad and Medic O'Neill enter SCP-30000. Commander Falk, Beta Squad, and other members of Epsilon-55 remain within the Mao.
E-01: Describe your surroundings.
ALPHA-3: Standard surroundings. An unfathomably thick trunk, branches the width of school buses, and a milky void beyond it all.
ALPHA-2: Scenerys nice and all, but I thought we kil- terminated anomalies, not explore them.
E-01: White Rabbits were pre-occupied, and our expertise with mythological anomalies made us a good fit for this job.
ALPHA-5: We have a body here.
Alpha-5's bodycam shows a cadaver of a large (approximately 5m in length) squirrel. The body is hanging on a smaller branch, and is in a severe state of decay.
ALPHA-4: Shit, that's massive.
ALPHA-1: Language, Link. Rain, get some photos of it. I'm sure they'll send someone to take some samples. Mona Lisa, come with me.
ALPHA-5: Roger.
Alpha-5 and Alpha-1 begin to descend to a lower branch while Alpha-3 took photos of the cadaver. Alpha-2 and Alpha-4 begin to take samples from SCP-30000's trunk and branches.
ALPHA-1: Link, we got a Way down here. What can you tell about it?
Alpha-4 can be heard struggling with his measuring equipment.
ALPHA-4: It's, uh, EDL 8. We haven't done any major explorations of it just yet.
ALPHA-1: Alright. Permission to enter, Falk?
E-01: Permission granted. Beta Squad is mobilizing.
BETA-1: On our way.
ALPHA-1: Squad on me.
Alpha-2, Alpha-3, Alpha-4, and Medic O'Neill join Alpha-1 and Alpha-5. Beta Squad and Medic De Graaf enter SCP-30000 and join Alpha Squad at the entrance to EDL-30000-8.

Item#: SCP-30019
| Containment Class: Euclid |
Level 3/30019 |
| Object Class: Undisclosed |
Classified |
| Assigned Site |
Site Director |
Research Head |
Assigned Task Force |
| Site-78 |
Fernanda Cortès |
Charles Calvin |
MTF Gamma-78 |
Special Containment Procedures
MTF Gamma-78 ("DARE To Be Free") is to monitor GoI-2722 ("Los Ratones")'s activities within Mexico City and the surrounding area. Under no circumstance, is MTF γ-78 to disrupt or engage with Los Ratones. Instead, the Task Force is to attempt to identify the Knock required to access SCP-30019.
If access to SCP-30019 is achieved, MTF γ-78 is to alert Site-78 Director Fernanda Cortés, who in turn would commence Operation 1521, which is detailed in Addendum 30019.1.
When SCP-30019 is under Foundation custody, attempts are to be made to ensure that the method to access the anomaly is restricted only to individuals within the Foundation.
Description
SCP-30019 is a pocket dimension, connected to the city of Mexico City, Mexico. While multiple Ways have been located throughout the city that connects to SCP-30019, the Knock required to travel through them is unknown.
SCP-30019 is a perfect replica of the Mexica altepetl of Tenochtitlan as it was in late November 1519. It is believed that SCP-30019 was artificially created by priests within Tenochtitlan in response to Hernan Cortés taking Motecuhzoma II hostage. Currently, SCP-30019 is inaccessible to The Foundation and is under the ownership of Los Ratones, a paranormal drug cartel. As such, all information regarding the interior of SCP-30019 has been gathered from activated sleeper agents within the cartel.
Prior to Los Ratones uncovering SCP-30019, the anomaly was inhabited by the descendants of Nahua within Tenochtitlan, who sought refuge within it during the Siege of the Tenochtitlan. The original population still resides within SCP-30019, but are under strict control by Los Ratones.
The majority of the four zones of SCP-30019 is accessible to the general public, with the only areas restricted to the original population. These areas are what would've been Tlatelolco (which is used by Los Ratones as a base of operations) and the centre area, where the majority of the public buildings, palaces and temples were constructed.
SCP-30019 lacks a day-night cycle. Instead, the sun is consistently within the noon position in the sky and is considerably closer to the Earth than it is in baseline reality. No stars are visible from SCP-30019, even when high-power telescopes are utilised.
Beyond the city, in Lake Texcoco and the coast, Hernan Cortés' forces can be seen, which consisted of thirteen ships, horsemen, and foot soldiers. These forces constantly circle SCP-30019, but never come closer than 5km.
The bridges connecting SCP-30019 to the shores of Lake Texcoco are still intact and can be traversed for the most part. If one reaches the end of the bridge, they will be transported to the closest Way in Mexico City. Because of this, it is impossible to leave SCP-30019 and explore the rest of the region.
Every week, at what would be 1300 CST in baseline reality, an individual will manifest within the centre area of SCP-30019 on Wednesday. This individual referred to as SCP-30019-A will be dressed in a uniform consistent with Spanish soldiers in the early 16th century. Between the hours of 1330 and 1830, SCP-30019-A will visit each building within the area, starting at the Sun temple, and ending at the Templo Major. Once SCP-30019-A reaches the base of the Templo Major, SCP-30019-A will remove their clothes, stripping down to their undergarments. SCP-30019-A will then begin climbing the temple, muttering a prayer in a mix of Spanish and Nahuatl. Once SCP-30019-A reaches the peak of the temple, it will travel to the shrine on the left side, which was dedicated to Tlaloc. SCP-30019-A will ensure that the brazier within is still lit, before moving to the shrine dedicated to Huitzilopochtli. Once inside, SCP-30019-A will lay on the ground, and produce an obsidian dagger. After reciting a prayer to Huitzilopochtli in Nahuatl, SCP-30019-A will self-terminate.
Following this event, it will rain for approximately 5 hours. Once the rain subsides, SCP-30019-A's corpse will sustain damage similar to third-degree burns. The corpse will rapidly decompose, vanishing by the following day.
Addendum 30019.1:
Operation 1521
If access to SCP-30019 is obtained, the following task forces are expected to mobilise and report at Site-73:
- MTF Epsilon-11 ("Nine-Tailed Fox")
- STF Epsilon-55 ("Devil May Care")
- MTF Nu-7 ("Hammer Down")
- MTF Pi-1 ("City Slickers")
- CTF Omega-13 ("Godless Heathens")
As STF ε-55 is expected to arrive on-site sooner than other Task Forces, ε-55's Alpha Squad will enter SCP-30019 and scout the area, compiling a report on Los Ratones forces within. The report will be reviewed by the commanders for the Task Force, and, if the situation is favourable, will proceed with Operation 1521.
Battalions from MTF ε-11 and MTF ν-7 will lay siege on SCP-30019, with STF ε-55 and MTF π-1 supplementing the main force. CTF ω-13 will station themselves near known Ways that connect to SCP-30019 and terminate any individuals who attempt to escape. Care is to be taken to target only Los Ratones members and minimize the damage done to the general population and infrastructure.
Once SCP-30019 is under Foundation control, Class-A amnestics are to be administered to the populace of Mexico City and the surrounding area. Non-anomalous members of Los Ratones who are captured are to be administered Class F amnestics and released into the general public. Captured Anomalous members of Los Ratones are to be administered both Class-C and Class-G amnestics, with a focus on the events of Operation 1521 and the existence of SCP-30019. These members are then to be released in or near Portland, Oregon; Portland, Maine; Isle of Portland, United Kingdom; Backdoor Soho, Eurtec, or La Rue Macabre.
Addendum 30019.2:
Related Documents
Multiple documents from multiple groups have been recovered referring to SCP-30019. Following is an account from a Spanish soldier (translated from its original language to Modern English), the subject of which is theorized to be SCP-30019's creation.
Account of an Unknown Spanish Soldier, 1520
Blessed Mary, Mother of God, please have mercy on our body and our soul.
I pray this letter reaches you in good faith, Cortés, for is the news I bring is troubling me greatly. I hope you do well with what I am about to tell you.
Almost a fortnight ago, after you had taken control of the unruly Indios, I saw one of the heretic priests talking to one of our own. Juan de Palencia, I believe. I watched as the Indio took Juan, leading him away to their blood-caked temples in the centre of their city. I am unsure why he would let such a savage man take him anywhere, or even speak to him for that. Curiosity took over me, and I followed them.
I followed Juan and the heretic up the steps to the Templo Mayor. There, in the rightmost shrine, I watched the pagan ritual unfold.
Juan stripped down to only one layer of clothing. He laid down as the heretic pulled out a blade made of obsidian. He held the knife over Juan and spoke in his savage tongue. Once he was finished, he gave the knife to Juan, who thrust the blade through his chest. I was infuriated, and was about to make myself known when it happened.
I watched as Juan's body began to burn, almost as if it had been cast into a fierce flame. The heretic continued speaking in his uncivilised ways. As Juan was reduced to ash, the heretic vanished. Fearing that I had witnessed Devil worship, I muttered a prayer as I ran back to our encampment.
I hope you know what to make of this horrible paganism, Cortès. God bless you.
The account never reached Hernán Cortés, instead being intercepted by GoI-890 ("Buscadores de Dios en Nueva España"), a now-defunct paranormal organisation operating in New Spain.