By J. Edward Tremlett


Brownsville, Texas has a problem - its name is Matamoros.

Located just over the Rio Grande, the border town is boon and bane. It brings business as people travel to and from the United States, but it also brings drugs, violence and narco-gangs.

There is yet more trouble: a week ago, five Brownsville residents were slaughtered over five nights. The bodies were left in shocking condition, with parts torn out or wholly removed. And the only living witness is insane, talking of “Chupacabra” - the legendary goat-sucker.

Given the suspicious resemblance to certain cult slayings in Matamoros during the 80’s, Brownville’s authorities think the murderer could be a narco-gangster. To avoid a panic, they are currently sitting on that, along with information concerning the state of the bodies - especially how they were sucked dry of blood…

Police Friendly Lt. Jon Alvarez has contacted Delta Green because this is “odd,” and - like many border residents - he has heard stories about the Chupacabra. More importantly, he needs close-mouthed outsiders who can help solve the problem before he has to reveal the state of the bodies. Once he does, the cult “connection” may inflame the media, and all hell could break


Hell is upon Brownville, already. The Chupacabra is real: a dangerous predator from the Astral Plane. It has made a new home in the border town after being accidentally kicked out of Matamoros.

The Chupacabra is a remnant of Matamoros’ infamous Constanzo/Aldrete narco-cult. Mexican authorities were convinced the 80’s cult’s gruesome rituals were merely to scare competing drug traffickers. Those within Constanzo’s inner circle knew better: through his Palo Mayombe, he WAS in league with power.

Constanzo brought the Chupacabra into this world during a ritual to his chosen Patron. The creature wasn’t what Constanzo’d expected, but it had power, and shared its new master’s tastes. An iron cauldron (nganga) filled with viscera, blood and crushed insects linked the Chupacabra to this world, and it served the cult well.

When the police came too close, the cult fled for Mexico City - there to be shot down and arrested. The Chupacabra and its cauldron were left behind, but it has outlasted its master by almost two decades due to its predator’s caution… and the Matamoros Police’s callous attitude towards missing, dead and mutilated non-anglos.

Now, things have changed. A holy Relic (with odd, trans-planar properties) has been moved from Mexico City to the Cathedral of Nuestra Señora del Refugio for safekeeping while its normal home is renovated. This has created a massive “bubble” that the Chupacabra cannot operate in - a bubble that stops at the banks of the Rio Grande.

Pushed North of the border, the creature holed up in a poor part of Brownville, where convenient victims were plenty. It sated itself on the first five victims to try and make a new nganga. And it plans to binge-feed every few days, returning to Matamoros only when the Relic leaves, three
years from now…


Lt. Alvarez runs considerable interference for the Investigators. They are allowed to see the autopsy reports, view the bodies, inspect the murder scenes and talk to the survivor, should they wish it. All he asks is that they remain as legal as possible, stay discreet and report “weird” things only to him.

The five bodies are sickening (1/1d4 SAN): pulverized by heavy blows to the head, ripped apart, and missing brains, hearts and intestines, along with lengths of their spine. They have also been drained of blood through an odd, circular “rasping” puncture in the neck about the circumference of a pop can. Alvarez thinks the mutilations were done post-draining, based on the
crime scene’s relative lack of splatter.

(Extemporize names, times, dates and crime scenes, but only one had a connection with narco-gangs, and with the exception of the first victim they were alone in their buildings when killed.)

The first victim’s girlfriend was driven insane by what happened. When “calmed,” she says “Era el Chupacabra. Caminó del aire y tomó mi Jaime. Rompió su cabeza y tomó su cerebro…” before going back into hysterics.

(“It was the goatsucker. It stepped out of the air and took my Jaime. It broke his head and took his brain…”)

The crime scenes are within three blocks of one another in a slum Brownsville refers to as “shit town.” There is no sign of doors or windows being forced, or any forensic evidence of an intruder. There is also no sign of the missing body parts - not even a blood trail.

If Library Use is used, consider which language. English turns up only:

  • Details of the Matamoros cult and its news trail (see RESOURCES)
  • Info on the Chupacabra (RESOURCES)
  • Info on Palo Mayombe (RESOURCES)

Spanish turns up:

  • Twenty years of similar deaths in Matamoros, courtesy of gory Mexican crime tabloids (EXTEMPORIZE - 1/1d4 SAN to read)
  • The arrival of the Relic in Matamoros the day of the first murder. (EXEMPORIZE)

Alvarez’ help vaporizes south of the border. If the party ventures into Matamoros, they must play tourist, hiding their guns and badges. The city’s police are near-useless, but can be bribed for “unofficial help” (half-assed protection and tour-guiding)


The Time Factor / Media

Lt. Alvarez can’t sit on the gory details forever. The Investigators probably have 72 hours, and then media attention explodes. Phenomen-X sends a crew in to “report” - causing several problems if the Investigators have previously encountered them…


These murders are causing problems for them, so they have more people in town, dealing with it. This consists of well-armed thugs torturing and dismembering any “suspects” (settling scores along the way).

The party may run into them while following their sloppy trails of bodies, and they won’t want to cooperate. Worse, they may attract the Chupacabra’s attentions. And if the party goes to Matamoros to investigate, they may encounter them again…

The Monster

Sooner or later, the party comes across their quarry. They may find its nest in shit town: stolen body parts festering in a bucket - its sad attempt to make a nganga. Or they may simply get “lucky” and find it feeding.

The creature’s abilities may completely surprise them, allowing it to maim or kill before vanishing. Once it knows they’re hunting it, the Chupacabra begins hunting them…


  1. Killing the Chupacabra: This is the hardest choice: it could be anywhere, watching, and only an obscenely lucky shot can kill it. Offensive magic works, but it could vanish once it’s been wounded, and may “tag,” ambush and kill the one who hurt it…
  2. Banishing the Creature: Research into Palo Mayombe or the cult’s history reveals the importance of cauldrons. The Chupacabra’s cauldron is still in Matamoros’ “bubble,” which makes its destruction/defiling much easier. But finding it means talking to the locals, which possibly attracts the narco-gangs’ attentions.
  3. Removing the Relic: The Investigators could reason the link between the Relic and the monster’s appearance in Brownsville. If the Relic is removed from Matamoros, or destroyed, the Chupacabra returns to its cauldron, and previous hunting grounds.

Tampering with the Relic requires going into a poorly-guarded, but much-frequented, tourist attraction and smashing its glass box in the nave. The faithful will not be amused…



  • Killing the Chupacabra, or destroying its cauldron (banishing it) +1d10 SAN.
  • Merely sending it back to Matamoros +1d4 SAN.


For the Chupacabra, use the vampire from Call of Cthulhu, with INT 12 and POW 16. Every time it embodies in this world, re-roll its STR, CON, SIZ and DEX, adjusting its Damage Bonus and HP accordingly. It can increase its STR by drinking blood while embodied. These extra points expire after an hour.

Embodying costs 10 MP. Returning to the Astral Plane costs nothing, but it must spend another 10 MP to return. It can take things with it into the Astral Plane, which is how it moved the recent body parts, but must re-embody with them: if they are left behind in the Astral Plane, they’re lost.

It cannot “see” out of the Astral Plane, but can spend 1 MP to either sense the presence of alone humans, or “tag” someone it’s encountered. Once someone’s been “tagged,” the Chupacabra always knows where he is.

If the Chupacabra is dropped below zero hit points, it disappears into the Astral Plane, but can Embody again. If it is dropped to EXACTLY zero hit points, it is destroyed, leaving a grey-black, bubbling smear.

It attacks with a vampire’s bite and claws, has no armor and cannot use a gaze attack. It knows no spells, and is vulnerable to magic.

It costs 1d4/1d8 SAN to see the grey, lamprey-mouthed loping horror with all-too-human eyes. Watching it feed is 1/1d6 SAN


Brownsville map:,+TX

Matamoros’ Visitors Guide:

Constanzo/Aldrete Cult’s history:

Contemporary Articles on Matamoros slayings:


Palo Mayombe:

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