This article originally appeared in Pyramid #3

Designer's Notes:
GURPS War Against the Chtorr

by C.J. Carella

It all started at a convention in Baltimore. I had walked into a discussion about writing for GURPS, hosted by Steve Jackson and Loyd Blankenship, which I had attended mostly to meet the guys who had launched my writing career. Toward the end of the talk, Loyd mentioned off-handedly that they were looking for a writer to do a GURPS book based on David Gerrold's War Against the Chtorr series, the award-winning novels A Matter for Men, A Day for Damnation and A Rage for Revenge.

The world froze for a second as I said to myself, "Wait a moment, I've read those books, and I liked them." Actually, I had read only the first two books, and hadn't gotten around to reading the last one. I didn't say anything during the convention, but as soon as I got back home I bought the last book, and re-read the other two.

I remembered the first two books as an interesting twist on the old alien invasion story, as well as the harrowing tale of a man facing the threat. After reading the whole trilogy at once, from a gamer's viewpoint, I realized there was more to the novels than I had first thought; a world where survival itself was a victory, where monsters roamed the ruins of civilization and the survivors had to cling to sanity as they struggled on. There is outlandish adventure, deep characterization, exotic alien ecologies and devastating technological weapons. I could sense the possibilities clicking in my head as I read on.

War Against the Chtorr describes a 21st-century Earth in the middle of an alien invasion. Unlike your typical UFO attack, however, these aliens somehow introduced their ecology -- a vicious and deadly ecology -- onto our planet.

The invasion started with a series of plagues that killed well over half of the Earth's population. The alien ecology then spread, killing native species and replacing them with Chtorran plants and animals. The size and scale of the alien infestation grew, from red kudzu in Lousiana to black and shiny millipedes across half a nation... and then the worms began appearing.

Spearheading the invasion were giant purple caterpillars -- what scientists would come to call gastropedes, and the rest of the world would name worms. The idea of a giant caterpillar scaring the average gamer, after dealing with vampires, lichs and the occasional minor deity, seems less funny when you realize that the critter in question is 20 feet long, has a mouth three feet wide, and sharp, rending teeth circling its maw. Then throw in the fact that it's virtually bulletproof and can charge you at 60 mph. These worms were terrifying. They were also seemingly designed to prefer humans for food.

As soon as I got the contract, I started re-reading the books (yet again -- I probably read the whole trilogy seven or eight times, and sections of it got even more readings; it is a credit to Gerrold's writing that I never got sick of it) while taking notes on every important detail. These notes were finally compiled into an index which gave me page numbers dealing with any possible subject found in the novels, from the future history of the U.S. to the worms' dancing rituals. Then I started writing the book.

Monster Design 101

Translating the Chtorran worms into game terms was a toughie. Most of my players (and, honestly, myself) had never been too impressed by animals in GURPS, at least when it came to combat. Simply put, even a Tyrannosaurus Rex isn't as dangerous as a couple of humans with assault rifles. To remedy the situation, I designed the Chtorran animals to be, pound by pound, the most deadly predators ever encountered in this game system. They're so tough they don't need brains... but they're just intelligent enough as individuals to be highly unpredictable.

The playtest sessions I ran bore this out: the PCs were armed with anti-tank rockets, flamethrowers and TL8 assault rifles with a rate of fire of 2,400 rpm (that's 40 bullets per second). When it was over, the shell-shocked survivors had seen one third of their platoon lunched on by a swarm of animals that came from a pretty copse of trees. They had witnessed in loving detail their commanding officer being engulfed by the gaping jaws of a burning, but far from dead, gastropede. There weren't many overconfident players left after that first little encounter. They wanted bigger guns, smaller monsters and the GM to tell them that it had all been a bad dream. The PCs didn't want to go back out there, but they realized that the worms were the biggest danger their planet had ever faced.

Besides the worms, the Chtorran ecology is a multifaceted, colorful and almost universally dangerous creation. Dozens of alien critters, from the tiny stingflies to the cute bunnymen to the ship-eating Enterprise fish, are described in the books.

This is one of the most exotic and dangerous alien environment I have ever read about. I believe that GMs and players who try it out will agree. Its danger lies not only in its viciousness, but in the damage it has inflicted upon the Earth. The green planet is slowly dissolving into a purple haze.

On the Brink of (World) Insanity

Four Chtorran Jokes

Question: "What does a Chtorran call a rabbi, a priest, and a nun?"

Answer: "Lunch."

Question: "What does a Chtorran call the U.S. Army?"

Answer: "Lunch."

Question: "What does a Chtorran call your momma?"

Answer: "Lunch."

Question: "What does a Chtorran call a vegetarian?"

Answer: "Salad."

I'm assured it's all in the delivery...

There is more to the world of War Against the Chtorr than the super-monsters, however. The survivors of the plagues have suffered the worst mass shock in history. Everybody has lost someone close and seen more destruction than any other society in history, including Europe during the Black Plagues.

Then, they have had to deal with the unsettling knowledge that the Earth is being "Chtorraformed" by the invaders. The only place human-kind has in this new environment is as cattle.

This is enough to make most people just a little insane -- some more than others. The heroes have to fight their own inner demons as well as the aliens. Lose either battle and the world will belong to the Chtorr.

The potential for roleplaying complex characters is enormous. Here is a background that could satisfy the most bloodthirsty hack-and-slashers and the most sophisticated roleplayers, all in the same campaign.

Of Voices in the Head, Robots, Jets, and Other Toys

Gerrold, like any good SF writer, has also filled the series with wonderful gadgets of the near future. From assault rifles that can chew through brick walls to sentient computers, the technology of Chtorr can become an enriching addition for any science fiction game.

Amongst other things in the book, you will find the Telepath Corps, an organization whose members are hardwired into an wireless network, moving consiousnesses between "nodes" (read, bodies) at will; robots of all sorts, from sophisticated killing machines to simple household models, are also described. There are some devastating weapons pulled from the novels -- do you prefer your enemies blown to bits, burned to a crisp, irradiated to death, or frozen solid?

I was fascinated by the wealth of technology described in the novels. Many of the ideas I found in the series have served me in designing my own GURPS Cyberpunk campaign, even before throwing in the purple monsters.

Putting It Together

Before writing the book, I had to decide what gamers would want in a sourcebook based on an existing fictional background. Some of the buyers would have read the books, while others might be interested in the concepts without any previous exposure to the series. I tried to concentrate mostly on the elements that would be most useful to people running and playing a game -- flavor, setting, background info, and specific statistics, in that order. I also had to deal with what the books did not say. There are a lot of unanswered questions in the War Against the Chtorr -- are the worms intelligent, how did they get here, are there real Chtorrans -- including many that will not be answered until the last book is written. In most cases, I left the choice of answering them in the hands of the GM, to better surprise the players.

In the middle of the project, the fourth book in the series, A Season for Slaughter, came out and SJG sent me an advance copy of the novel. I changed the background material to conform to the new arrival. Steve Jackson also got some material from the fifth novel, A Method for Madness, coming out in 1994. This book will answer a lot of questions; I added bits from it here and there, as well as a section on creating new Chtorran creatures.

Eventually, after months of thinking, writing and breathing worms, worms, worms, the book came together. Being a crossover/gender-bender aficionado (what others might call a freak), I felt the book would not be complete without some notes on integrating the Chtorr and their deadly environment into other GURPS worlds. The Campaigning chapter has ideas for combining the Chtorr with several worldbooks, from Supers to Illuminati. I didn't have the heart to suggest a Chtorr-Martial Arts crossover...

GM: "The worm rears up in front of you, dripping purple goo and making an evil chittering noise."

Arnie Goldman, the Terminator: "I kick the Chtorran."

GM: "The Chtorran eats your leg."

Arnie: "Oy vey."

I like to think of the readers of this book as people standing in line to ride Space Mountain for the first time. I'll try not to let them down. But if they are not careful, something they disagree with may eat them.

Article publication date: October 1, 1993

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