5 November 2000 1000H. Kalisz.

For everybody’s safety, every member of Maks’ Kalisz away team had to be quarantined. Maks had a unit to run – 300 Americans now – and now he and his best men were behind plastic sheeting, tended by medical personnel in disposable garments. The party had been exposed to bubonic plague.


0004The session last night involved several topics. This post is a deep-dive into the game’s disease rules, and situational rules-making.

My original Settlement Crisis roll for Kalisz (Twilight: 2000 v2.2 rulebook, page 271) was 10: Disease. Typically the GM would go next to the Settlement Diseases table (page 274). But I used the Encampment Diseases table instead, accounting for the squalid state of Kalisz during the months’ long siege.

I rolled 9: Bubonic Plague.

Preparing for this session I read up on the T2000 Disease Rules, followed up by reading medical summaries of the plague specifically.

“The two plagues (bubonic and pneumonic) are (…) essentially lethal on a failed recovery roll with extended debility periods of 15 weeks each.”

See Ranting Savant’s Bring Out Your Dead (Disease in Twilight: 2000) for an overview of T2000 disease rules.

Bubonic plague is a disease of declining odds. By Phase II of the infection, antibiotics are half as effective as they were in Phase I. 

“Yersinia pestis is the nastiest thing alive… It’s the most virulent bacterial organism known to mankind.”

“One out of seven persons infected dies, even with aggressive treatment.”

UChicago Medicine

No preventative medicine in Twilight 2000

The disease system in the T2000 game presumes that:

  • A character will be exposed to a pathogen (contaminated water, for example).
  • Infection check is rolled (this would be unbeknownst to the character).
  • A few days later the Incubation period ends, and symptoms begin to manifest. This is when the PC realizes something’s wrong.
  • The party medic makes a medical diagnosis check, applies treatments, and the patient attempts a recovery.

Our party’s situation was different. For dangerous microbial pathogens, a preventative regimen of antibiotics is most effective promptly after suspected exposure.

Bubonic plague is one of those diseases, where time is of the essence. The away team was under quarantine for observation and antibiotic treatment within 2.5 hours of possible infection. The Incubation period for Bubonic Plague is 1D6 days.

The T2000 disease system doesn’t allow for a preventative regimen in normal game play: Antibiotics do not provide a bonus to the Infection roll. This covers most disease encounters in the game, which are discovered after the Incubation period. The party’s knowledge of their exposure in Kalisz was atypical, however. I’d have to house rule this situation.

I followed the disease’s Phase bonuses backwards to account for a preventative regimen of antibiotics implemented soon after exposure.  The antibiotic bonus would be applied to the Infection roll and that bonus would be double Phase I‘s antibiotic adjustment.

“It is recommended that antibiotic therapy be started as early as possible. A delay in antibiotic therapy will result in an increase in bacterial biomass, and in a more harmful subsequent inflammatory response.”

Click to access 1461.pdf

“Persons in close contact with pneumonic plague patients, or persons likely to have been exposed to Y. pestis-infected fleas, to have had direct contact with body fluids or tissues of a Y. pestis-infected mammal, or exposed during a laboratory accident to known infectious materials should receive antibiotic preventive therapy, if the exposure was in the previous six days.”


Bubonic plague is spread by rat-borne fleas. Members of the away team may or may not have been exposed to flea bites. This is unlike contaminated water, for example, where anyone who drinks is susceptible. 

Given the randomness of fleas, and the relatively brief time the party had in infested areas (perhaps 5-10 minutes altogether, including homeless camp, and especially inside the detention center):

I set a simple roll for a 50% chance for each member of the away team to have been contaminated with fleas.

“At the present time, the circulation of Y. Pestis has been detected within the populations of more than 200 species of wild rodent inhabiting natural plague foci on all continents, except for Australia and Antarctica, and the transmission of plague is provided for by a minimum of 80 species of flea.”



For those who fail the Infection roll, standard Disease recovery rules apply (pages 244-5).

As it turned out, 3 of the party members were exposed, bitten by fleas. They all passed their Infection rolls, however.


Team & CON Exposure Inc. (days) Infection Phase I Phase II
Maks 9 yes no
Wojciech 8 no
GDW 6 yes no
Barna Aron 5 no
Observer 5 yes no

The Attribute CON gets heavy use throughout the T2000 disease system. Fortunately for our party, none had a CON less than 5.

The party was plain lucky that they a) were aware of the exposure immediately, and b) were so close to good medical facilities. An undetected, untreated plague is a mortal threat in the game.

Even still, a few rolls could have gone wrong this evening, leaving us with gravely ill PCs circling the drain over the next couple of game weeks. I was a bit nervous, I’ll confess. The party had repeatedly survived armed threats all over Poland, only to be cut down at the end by plague?

They’ll be alright. However, the characters don’t know they’re out of the woods.

Maks and his best people are stuck in quarantine for 6 days, to wait out the incubation period. They must be in Bremerhaven in 10 days. So the first part of their rail journey will be awkward and confining.

And there were other loose ends to tie up: Personnel problems. Gear and food to load up. And lastly pick a rail route west around Warsaw Pact formations.

Follow-up next post.