present location in physical space but located in a future time period. 
The amount of time into the future traveled by the subject is related 
to the amount of energy input into SCP-2003. An approximate 
estimate of 3500 kWh in order to send a subject seven months into 
the future has been documented; however, this relationship 
becomes unpredictable at higher energy levels. 


Subjects using SCP-2003 will exist in the time period to which they 
have traveled for a duration ranging between 15 and 38 weeks 
before spontaneously returning to the time period of origination at a 
point coterminous with their present location. For safety purposes, a 
secure location has been established for operatives to use while 
waiting for return to their time of origin. Operatives must report 
subsequent to experiencing 98 days after SCP-2003 activation. 


While SCP-2003 enables chronological travel for living subjects, the 
activation process has proven severely damaging to most types of 
animal and plant tissue. The only exception documented to date has 
been tissue related to the animal nervous system. As a result, 
personnel designated for SCP-2003 travel must be prepared 
accordingly (see additional documentation for details). 


Testing has shown that under current conditions, SCP-2003 remains 
functional and under Foundation control through December of 2348. 


Addendum 2003-A: General Results of SCP-2003 Research 


Initial deployment of SCP-2003 began in 1995, using modified 
personnel to observe future conditions and events. The purpose of 
these deployments was to confirm the nature of travel using 
SCP-2003, and if possible collect data allowing the Foundation to 
better mitigate future anomalous phenomena. The results of these 
initial exploratory missions demonstrated several crucial principles 
for understanding observation of future events: 


Data collected using SCP-2003 is imprecise. Early exploratory 
missions yielded copious amounts of data regarding what appeared 
to be future events. However, subsequent observation has 
established that these observations are not entirely predictive. For 
instance, while collected data allowed Foundation assets to prevent 
a major security breach of SCP- at Site-19 in 1997, a catastrophic 


earthquake originating off the coast of the Western United States 
(observed directly by several field agents using SCP-2003) failed to 
occur as predicted in 1999. As more data has been collected, meta- 
analysis has properly contextualized observations and has assigned 
a probability of occurrence for major events in the future. 


Certain individuals appear to affect causality disproportionately. As 
Foundation cataloguing of possible future events increased following 
the completion of more exploratory missions, certain events were 
deemed to be undesirable for the Foundation's mission. Early 
attempts to influence these events met with mixed success; while 
manipulation and/or elimination of some individuals achieved 
mission goals, other Foundation attempts to influence events failed 
to alter outcomes at all, even when several actors deemed to be 
essential were liquidated. Meta-analysis has determined that in 
some cases, the actions (or indeed very existence) of individuals 
with no discernible relation to major events, sometimes in regions 
thousands of kilometers away, have profound and immediate 
impacts on these events. Since this discovery, research staff has 
maintained a database of these individuals. 


Few cohesive "futures" are tolerable to the continued beneficial 
existence of humanity. While observed conditions exhibit a tendency 
towards variation upon each exploratory mission, a number of 
loosely consistent "timelines" have been observed, cataloged in 
Foundation databases as Determinative Sets. Most Determinative 
Sets consist of a collective future that either renders Earth 
unsuitable for human civilization (and in some cases life in total), or 
results in conditions directly inimical to the well-being of most of 
humanity. The reasons for the relative paucity of long-term survival 
scenarios, if any exist, are unknown at this time, as is any 
connection to the steadily-increasing observation of anomalous 
phenomena documented across the Foundation. 


+ TS/2003/EYES ONLY 
Addendum 2003-B: Preparation of Personnel for Use 


Due to the nature of SCP-2003's effects on human 
anatomy, special preparations must be made in order to 
properly outfit personnel for chronological travel in a 


condition suitable for both survival and ability to carry out 
mission objectives. Because of the sensitive nature of 
tasks necessary during SCP-2003 missions, D-Class 
have been deemed unsuitable subjects. 


Preference for SCP-2003 subject recruitment is to be 
given to personnel nearing or past official retirement age. 
In cases where personnel have been diagnosed with 
terminal illness that does not impair neurological or 
cerebrospinal function, preference may also be granted. 
Personnel volunteering for SCP-2003 travel are to be 
moved to the Tier VI pay scale for the duration of their 
assignment; any survivors are entitled to an Elevated 
Benefits Package distributed through normal clandestine 
channels. 


Prior to outfitting, selected personnel are to undergo 
extended sensory deprivation training, concurrent with 
training in simulated environments analogous to those 
experienced by occupants of the XX890-V Life Function 
and Observation (LFO) system. During this period, 
personnel must undergo a prophylactic course of 
antidepressants and antipsychotics as overseen by 
medical staff. 


Upon completion of training regimens, personnel are to 
have all brain tissue, nerves, and associated nervous 
system structures surgically removed and transplanted 
into the XX890-V LFO system. All usable organs are to 
be harvested afterward per medical protocols. 


Current guidelines authorize the XX890-V LFO system 
and occupant for four uses of SCP-2003. When not 
engaged on missions, personnel are to be kept in an 
induced coma state, concurrent with research 
establishing 18 months as the median time period before 
communications and feedback from XX890-V LFO 
occupants become agitated and incomprehensible. 


The nature of the XX890-V LFO system is to remain 
classified and accessible only to senior personnel. 


+ TS/2003/EYES ONLY 


Addendum 2003-C: Overview of XN-SHEPHERD 
Program 


MEMORANDUM 

TO: Armed Site-47 Director - 
FROM: O5-7 

RE: DETERMINATIVE SET XN 


3 


Up to this point, all attempts at future 
intervention using SCP-2003 have been 
limited in scope and scattershot in nature. | 
have seen the wisdom in this approach; it is 
informed by painstaking contingency planning 
and risk/benefit evaluation. 


The last 18 months of reports, however, have 
promise if we are bold enough to seize the 
initiative. We may have found a way out, here. 


The price, though. There's always a price. As 
you well know. 


Consider this note an official change in policy. 
As of today, all efforts at intervention are now 
aimed at bringing about and preserving XN. 
Designated Magnifier Individuals associated 
with XN are to be protected from undue 
interference at the expense of all other 
priorities. In particular, Nuru Diagne must be 
allowed to die in the manner most 
observations have predicted for her. If 
anything at all changes in that regard, make it 
happen. 


| trust that you're familiar enough with the rest 


of the Determinative Sets to understand why 
we're going this way. 


One more thing: All communications, and | 
mean all, with anyone outside of Site-47 are to 
be cleared and routed through my office. 


+ TS/2003/EYES ONLY 


Addendum 2003-D: Listing of Known Determinative 
Sets 


Preferred Option: 


Designation Description Notes 
XN Currently See Addendum 
documented 2003-C 


reality. Society 
continues along 
established 
Foundation 
projections 
regarding 
economic trends, 
environmental 
factors, and social 
upheaval. 
Anomalous activity 
continues to 
manifest mostly 
consistent with 
present rates. 
Consensus reality 
maintained 
successfully until 
83345 Moore, a 
previously 
untracked asteroid 
22 km in diameter, 


collides with Earth 
in January of 
2349, killing most 
of humanity 
immediately and 
rendering the 
planet unsuitable 
for sustained 
human existence. 


Other Documented Determinative Sets: 


XB 


XE 


Designation 


Description 
Development of 
society continues 
in manner similar 
to XN until April 
23, 2017, whena 
gamma-ray burst 
originating from 
the vicinity of HD 
188753 directly 
strikes Earth. The 
burst lasts 2 
minutes and 38 
seconds and kills 


Notes 
Researcher, 
directly observing 
this scenario at the 
time of the 
gamma-ray burst, 
was the only 
known living being 
to survive the 
event, and was 
able to continue 
collecting data 
until his return 52 
days later. Study 


all known forms of of use of XX890-V 


life. 


LFO system for 
high-radiation 
environments 
pending. 


The election of Sir In all permutations 


William Entwistle 
as Prime Minister 
of New Zealand in 
2049, combined 


of this set, 
widespread public 
knowledge of the 
Foundation occurs 


with the birth of an precisely 86 days 


unnamed infant 
boy in Ahal 
Province, 


before the 
detonation of 
nuclear weapons. 


XH 


Turkmenistan on 
the same day, 
lead to an 
escalating chain of 
events culminating 
in a society- 
destroying nuclear 
exchange between 
the nations of 
Israel and Greater 
Indonesia in 2058. 
All Foundation 
attempts to 
interfere with 
either individual 
merely result in 
the date of the 
nuclear exchange 
occurring sooner, 
Between the years N/A 
2023 and 2034, 
world 
governments 
approach global 
affairs ata 
radically increased 
level of 
cooperation due to 
the onset of a 
highly virulent 
influenza epidemic 
that kills 
approximately 1.4 
billion worldwide. 
Throughout the 
2040s and 2050s, 
many longstanding 
ethnic conflicts are 
resolved through 
the intervention of 


XJ 


multilateral 
organizations, 
endemic poverty 
and hunger in 
areas such as 
sub-Saharan 
Africa and the 
Indian 
subcontinent is 
substantially 
decreased, and 
large-scale 
projects mitigating 
sea level rise are 
completed 
throughout coastal 
regions. On July 
29, 2059, the 
entire population 
of Earth 
spontaneously 
vanishes along 
with all known 
animal life, with no 
observed return 
within 
observational 
range. 

An entity later 


This scenario was 


confirmed to be anultimately averted 


exact duplicate of 
Dr. Masako 
Koizumi, one of 
the original 
researchers 
responsible for 
SCP- prior to its 
containment, 
appears within an 
inner security 


by staff sedating 
the duplicate of Dr. 
Koizumi, placing it 
into an XX890V- 
LFO platform, and 
transporting it in 
SCP-2003 using 
all available 
energy. Temporal 
complications from 


perimeter at this action are 
Armed Site-47 om unknown, but 
April 1, 2011. The presumably do not 
entity requests materialize prior to 
that Dr. Koizumi's 2349. 
scheduled 

euthanization 

elsewhere within 

the facility be 

cancelled 

immediately. As 

SCP- was not 

functional at the 

time of established 

containment, the 

means by which 

the entity is able to 

make this request 

are unknown, and 

presumed to occur 

in the future. 

However, due to 

the establishment 

of K-Failsafe 

Protocol Twelve, 

the request is 

impossible for 

Foundation 

personnel to 

comply with, 

resulting in an 

Alpha-8 type 

temporal paradox. 

This series of 

events repeats for 

an uncountable 

number of 

instances, 

resulting in the 

eventual collapse 


XO 


of spacetime as 
understood by 
humanity. 
Anomalous 
phenomena 
begins increasing 
in frequency by 
orders of 
magnitude 
beginning in 2037. 
The Foundation 
comprehensively 
loses capabilities 
to protect 
consensus reality 
by 2039 and world 
civilization 
undergoes a 
period of chaos 
and upheaval. 
Millions die in 
spontaneous riots 
and mass suicides 
become 
commonplace 
throughout the 
world. Numerous 
messianic 
religious 
movements 
quickly form and 
contribute greatly 
to civil conflict and 
internecine 
warfare. By the 
mid-2040s, 
several sects and 
remnants of 
national 
governments 


Due to the open 
nature of 
anomalous 
phenomena in this 
scenario, data 
collected is the 
most 
comprehensive of 
any Determinative 
Set, as Agent 

is able to work 
openly and 
unimpeded. 


XR 


successfully 
weaponize various 
anomalous 
phenomenon, and 
humanity is wiped 
out by 2048, with 
the exception of a 
small group of 
survivors 
sheltering in the 
remnants of 
Site-104. All 
contact with this 
group is lost upon 
their discovery of 
Wing K of 
Site-104. 

The population of [DATA 
Homo ignotus, EXPUNGED] 
long estimated by 
Foundation 
operatives to be 
approximately 500 
individuals, 
increases 
overnight to 
approximately 8 
million individuals 
in 2015. A short, 
violent struggle 
ensues between 
the combined 
forces of the 
Foundation and H. 
ignotus, with all 
means of 
resistance to the 
newly ascendent 
H. ignotus 
population 


XS 


systematically 
destroyed within 
three days. 
Humanity is then 


Researchers 
currently have 
divergent theories 
as to whether this 
Determinative Set 
is predictive of the 
intentions of the 
known H. ignotus 
population, with 
current theories of 


being supported 

the most. 

Determinative Set [LEVEL 4 
XS proceeds ina SECURITY 
manner similar to ACCESS ONLY] 
XN until an 

indeterminate date 

in 2019 when 

Armed Site-47 and 

all knowledge of 

SCP-2003 is 

apparently lost to 

the Foundation. 

Researcher is 

detained by the 

XS version of the 
Foundation during 

an observational 

mission in 2022 

and held as an 

SCP classified 

phenomenon until 

her return. 


XU 


Researcher is 
detained by XS 
Foundation 
personnel at point 
of entry upon 
commencement of 
her next 
observational 
mission, and 
returns with no 
retrievable data 
and portions of her 
brain tissue 
removed. No 
further information 
on Determinative 
Set XS is 
available. 

On February 17, 
2026, contrary to 
all astronomical 
models and 
understanding of 
both classical and 
quantum 
mechanics, the 
Sun suddenly 
collapses into a 
black hole despite 
not meeting 
commonly 
understood mass 
thresholds for 
triggering such an 
event. Despite the 
almost immediate 
cooling of Earth 
and all other 
planets in the 
Solar System to 


This Determinative 
Set is a subset of 
previously 
designated Set 
XT. XT was a 
future in which a 
single totalitarian 
regime had 
assumed control 
over the planet 
and targeted 
various 
"subversive" 
organizations for 
elimination, 
focusing on 
Foundation 
personnel in 
particular. 
Foundation 
researchers 
attempted to avert 


XW 


approximately this scenario by 
-270 degrees sending three 
Celsius and the | identified 
elimination of all) individuals from 
other forms of life, South Korea into 


humans are orbit on the 
unable to die, International 
maintaining Space Station. XU 


consciousness resulted. 
despite the lack of 

continuing 

biological 

functions and 

almost total 

cessation of 

molecular 

movement. 

Beings strongly | The last two 
resembling personnel sent to 
human-sized, observe 

animate versions Determinative Set 
of SCP- manifestXW (Agent 

in most major and Researcher ) 
population centers failed to return to 
on August 13, time of origin, and 
2019. Rather than are listed MIA at 
causing alarm, this time. 

these beings 

quickly become 

accepted by 

humanity after 

offering major 

advances in 

medical science, 

energy production, 

crop cultivation, 

and the arts. By 

the close of 2022, 

thousands of 

people willingly 


XX