Mothership: Gradient Descent Module Recap

What Is Gradient Descent?

I recently finished running a play through of the Mothership RPG official module Gradient Descent. Mothership is a sci-fi horror roleplaying game inspired by media like Alien. It makes heavy use of official and unofficial modules. Gradient Descent is the most recent official module and is “a sprawling sci-fi megadungeon inspired from fantasy rpgs, movies like Blade Runner, and comics like Blame!.” I had not run Mothership before this module, but the game was on my radar for a while after seeing some noise about it on Youtube and Twitter. I think the best way to summarize Mothership is to look at the designers’ original goal: “Survive, Solve, Save: Pick One.” I love that as a goal as it gets right at what good games are all about: hard decisions with interesting consequences. It also proved to be pretty true in our game!

How I Ran It

After here, this post contains significant spoilers for Gradient Descent. Don’t read further if you don’t want spoilers. Also don’t read this section if you played in my game and don’t want to see behind the curtain! You’ve been warned.


First of all, I knew due to time commitments and having a very long list of games I want to run, I would just be running the module itself and not committing to a larger Mothership campaign. I had no idea how many sessions it would take, but I wanted to just run through the content in the book, and to have the end state be the crew all dying or escaping the Deep. I knew there was a decent amount of interest among players in this module, and that not all of them would be able to play. I debated running a West Marches-style game, or running a tournament with scoring like the D&D Championship Series. In the end, players preferred simply running through in groups, so I let the first four interested players in and said I might run it again later for the others.

Given the pandemic, we played on Roll20. Roll20 was nice for this module because I could load in all the NPCs and maps ahead of time. I used player maps kindly edited by a member of the Mothership Discord to remove secrets and room names. Those were really handy. I understand they are working on an official player map also, which would be really helpful. I spent quite a while doing that to get it ready and then copied my game, so I have a template ready to go if I run it again. The Roll20 sheets for Mothership are quite good, so we were able to use those without much trouble. I coded some macros and rollable tables for some common rolls in Gradient Descent, which saved me some time but also caused a few headaches. It was nice to use them to wrangle the many random tables in the game.

Reading the module and Discord a bit beforehand, I made these choices for the game:

The Fate of Our Crew

Here’s a recap of what happened to our crew in our play through.

We played seven sessions with five players (including me, the Warden), with each session being around 3.5 hours with one 10 minute break. I’ll summarize by in-game day here, but most sessions lasted less than a day. By the end, one PC survived (kind of 😅) and four died. They did come really close to escaping the Deep, though! Literally one roll at the end could have change the entire outcome. How exciting!

Day One

Our crew started off in the Freezer, waking up from cryosleep in an unknown chamber with no memories of their past life. They had a small collection of items including a trinket and a patch, some of their only connections to their past. Our cast of characters was:

The crew also found a wounded diver, Lucy Espinoza, in one of the other cryopods. They successfully revived her and she explained the basics of the Deep and showed them the way out. Their goal was to get to the Bell to learn more and rest. They ran into a Ghost in the Machine on the way to Eden, but Hank’s player figured out that they simply needed “help repairing” a bulkhead to be satisfied and avoid violence. He “helped” as the rest of the crew flew past in zero gravity, successfully avoiding any damage. In the hatch at the entrance to floor two Dr. Weir found a combat shotgun and - strangely - a book with his name as the author on morality and artificial intelligence.

They met the Chosen androids defending their kingdom from the Fallen hoarde. Lucy told them to ask for an audience with their King. After he was satisfied they were not agents of the Minotaur, he let them pass through Eden. They made their way though the strange overgrown conference center and eventually found another Diver, Kira, resting at the statue in The Visitor’s Shrine 25C. After doing some poking around the statue and finding a strange drainage tube within it, they decided to leave. They found an exit and left Eden, finding a lift to floor one in the lobby beyond Eden.

They took the lift up to floor one. Here there was a Troubleshooter raid in progress. They heard them coming and looked for a hiding spot. Lucy and Kira took shelter in a conference room, but the crew didn’t like being cornered so they kept advancing. Eventually they found the security checkpoint 23A and decided to go through it in hopes the Troubleshooters would not follow. They gave up their weapons and headed through. I ruled that the laser cutter and hand welder would be allowed as they were more tools than weapons.

They found the Cubicle Farm 23B and some evidence that Divers had been there. At this point a contingent of security androids was dispatched to deal with the Troubleshooters. On the way they ran into the crew and a fight broke out. This fight was brutal because the PCs did not have any weapons. It involved a lot of hiding behind cubicles and grappling with the guards to disarm them. The PCs did manage to get ahold of the SMGs pretty effectively and eventually shot or pummeled the androids into submission, though one got away and they took a bit of damage. The fight took an entire session though because everyone was dealing low damage. It was a slog.

After the fight, the deep synthesized voice of Monarch, the station AI, broadcast to them over the PA system. “Ah, I see you have woken up. And quite a mess you’ve made. I hope you slept well. Are you ready to get to work? I have some business I’d like you to take care of.” The PCs agreed to hear him out. “The Mind Thief (Floor 3, Brain Construction) wants me dead. Despite my best efforts I have not been able to pin them down. Find them for me and kill them. Additionally, the Minotaur (Floor 2, Eden Labyrinth) is my child. It is also a failed experiment. I created certain failsafes to ensure I cannot kill it. But you can. I’ll pay you 5mcr upon completion of both tasks.”

The players were unsure about working for the station AI, so they didn’t give a straight answer. Monarch cautioned them to watch out for the Troubleshooters. They considered trying to get into the locked Escape Pod door, but instead they cautiously explored floor one. The Troubleshooters were investigating another section and they managed to sneak around them without being detected. They found Lucy and Kira’s body in the conference room, victims of the Troubleshooters. TERRA poked around in the rubble and found a backpack with some (faulty) medicine and shotgun shells. They also nearly got fried overturning a piece of melted slag that had an EMP grenade under it, but managed to dodge the blast. Jagg smartly welded a door shut to prevent being followed. They found the hanging corpse near reception and Dr. Weir’s cybernetic scanner reported an error…

They eventually found the Visitor’s Dock and were able to radio Arkady to come pick them up. He took them to the Bell and filled them in on some more background on how the Deep functioned and its history, including Monarch’s origin story. The crew decided they were tired out and didn’t explore the Bell, instead deciding to strap in and rest.

Day Two

After a full night’s sleep in the cold safety of the Bell the crew was ready to return. They knew they had a few options for how to proceed:

They traded some items with Arkady, stocking up on ammunition and rations. He dropped them back off at the Visitor’s Dock on floor one. They retraced their steps to the Cafeteria and explored a bit more without the pressure of a Troubleshooter squad on their tail. TERRA took the golden rat from the cafeteria.

Dr. Weir tried to hack the weapon recognition system, but after he failed, Jagg took the laser cutter to the turret system and blew it open. At this point, a Troubleshooter squad arrived again! Hank took immediate action and tossed a frag grenade down the corridor as they approached. The grenade exploded and caused a minor hull breach, causing all the airlock doors to do an emergency close. Dr. Weir narrowly made it out of the security station and back into the cafeteria as the door closed. Now trapped and unsure of the fate of the Troubleshooters, Jagg got to work laser cutting the door to the security station open. Eventually he cut a hole and the crew fled through it.

As they ran down the corridor, Monarch’s voice came over the speakers again. Fearing the damage they caused to the hull, Monarch announced that the crew was an enemy of the Deep and a reward would be offered for killing them. Knowing the Troubleshooters would likely not be far behind, the crew decided to take the other elevator down. They found that it only served floors 4 and 6, but decided they didn’t have much choice with Monarch’s recent announcement. They could at least look for the artifact experimentation room while they were there.

They took it down and arrived on floor four’s lobby with a sign announcing they had arrived at the Human Emulation Lab (HEL). There was a great moment where as soon as the doors opened they saw four security androids in strange glass bubbles serving as lookouts for the floor. They instantly prepared to open fire with their SMGs at the same time the up arrow on the elevator dinged, showing that it had been called from floor one.

Three members of the crew jumped out into the lobby, returning fire and taking cover. Dr. Weir decided to stay and try to prevent the elevator from bringing down trouble from floor one. He rode it back up and tried to hack it as it ascended. He got a critical success and now had full control over the elevator. He sent it back down to floor four as the rest of the crew was in a firefight with the androids.

Hank and TERRA smartly fled to the Server room to use the doorway as cover, only popping out to take quick shots at the stationary androids. Poor Jagg was overly optimistic however, and only took cover behind a bench. The four androids turned their SMGs toward him and he died in a hail of bullets. RIP.

William arrived on the scene to find Jagg dead. He also fled into the server room. After a round of exchanging fire the androids calculated victory was impossible and abandoned their posts, receding into the ceiling.

The crew looted J’s body and laser cutter. They then explored the server room, finding a mutilated corpse. On leaving another Ghost in the Machine haunted them, this one an angry scientist with scalpels floating around his head. He chased the crew around floor four and convinced several of them that they were being stabbed repeatedly with his advanced holographic technology. The Ghost attacked TERRA and they received a sudden shocking memory, seeing a screaming android child sitting on a stool being prodded and poked by instruments, a strange fleshy helmet on their head. Shortly after the Ghost did the same to Dr. Weir, who saw a group of android children playing, but suddenly a fight broke out and they started savagely fighting each other. The memory showed the viewer (they realized now it was the Ghostly scientist’s memory) scrambling to put on a strange heavy metal helmet hanging on the wall. After putting it on, the scientist looked back and saw the children quietly playing again. The crew shot back at the ghost without effect.

Eventually the crew found a decompression airlock and decided to cycle it to try to flee the ghost. Unfortunately the ghost was able to simply fly right through the door, causing several of them to question their sanity. They also encountered a strange figure in a dusty, hulking space suit standing motionless in the airlock. They eventually learned this was Dalv, Jagg’s player’s new PC. He sported a talon-like robot grip hand and quickly became known for his Zen koan-like proclamations and unflappable attitude.

After hacking the airlock to force it to open faster, the crew made their way through and found the Artifact Lab Observation Room. Hank saved the day again by comforting the distressed scientist. He and Dr. Weir eventually subdued the ghost with a group hug.

The crew got to know Dalv (as best they could) and explored the Observation room. They realized that this room showed them a feed of the observation room, but they didn’t know exactly where it was located. They knew it was on this floor and could see it was open to space. They considered trying to space walk or find a shuttle to find the opening, but decided to finish searching floor four for an artifact first.

They decided to check out the Human Emulation Labs next. They found a huge room full of child androids running through various mental and physical tests at great speed. Hank made himself at home in the 1950s nuclear household drama simulator, cracking a beer and watching some baseball. Dalv walked over to the glass cube of math geniuses and tapped on the glass much like a child would do at an aquarium. Dr. Weir tried to figure out how to snap a child out of their task unsuccessfully. TERRA just sort of wandered around until Hank got a bit freaked out by the androids and decided to take the TV out of the simulation room and invited them to join him.

A fun scene ensued where Hank taught TERRA about America’s favorite pasttime while Dr. Weir tried to figure out a way to get his hands on a logic core. He eventually used the mainframe to discover HEL’s sick secret: that the children had billions of past lives still inhabiting their logic core while they competeted to produce extremely intelligent and capable androids. He realized some of them wanted to be free of this hellish existence and decided to rescue one. Using his electronics skills he managed to hotswap a blank logic core for one of the children’s cores.

After successfully grabbing a core he and the others left HEL, checking out the last server room before leaving the floor. In here they found two escaped child androids playing dead under a fallen server rack. Hank shook them awake and grabbed them before they could run off. They were shielding a ball of wires that the crew quickly learned was one of the famed artifacts - though they had no idea of its function. They decided to take the kids with them and help them realize their dream of finding a new body and erasing all their tormented past lives for a fresh start. Hank started calling the kids Huey, Dewey, and Louie (in the chip), and it stuck.

With children in tow, it was decision time:

They decided they would rather not fight the Troubleshooters, so they took the lift down to floor six. They found a locker room and scavenged it. Dr. Weir found some snacks and unfortunately TERRA found a grenade rigged to explode when the locker opened. They nearly died, but Dr. Weir’s medical skills and a night’s rest with the door welded shut helped them survive.

Day Three

After an uncomfortable night on watch or sleeping on locker room benches, the crew decided to head to the Fuel Tanks room past the lockers. A quick peek revealed a huge poorly-lit room with some security androids in it. Looking to avoid conflict, the crew broke open their welded door and continued in another direction. Hank found some cigarettes in a staff lounge vending machine and smoked while the crew tried to figure out what was going on in a control room. Strange synthetic steel webbing covered several industrial control panels. Hank hesitated for a moment before deciding to brush them off and flip a few switches. He summoned a lift of unknown location to floor six and unlocked an Auto-Tug craft visible on some monitors in a nearby loading bay. After working the panels the crew heard a strange skittering sound from deeper into the floor.

Fearing the sound, the crew decided to backtrack and check out a local comms room. On the way they heard more skittering and increased their pace. They found a cramped comms room with a dusty terminal in a dead-end corridor. Hank jumped on the comms and decided to contact one of the corporate blockade ships, the Outpacer Rudi. He hailed one Captain Eno Valis, who after some negotiation, agreed to let them off the Deep in exchange for their artifact. They agreed to meet the crew in an hour in the floor six loading bay.

As soon as the call ended, a giant abomination came crashing around the corner in the hallway outside their room. An android torso with many eyes stood atop a strange pseudoflesh abdomen with eight sharp legs and a thorax pumping out steel webbing. This spider android came lunging at them. In the ensuing combat the crew took a few hard hits from its piercing legs, but they used the laser cutter and a few grenades to great effect, dealing significant damage to both the android and the hallway. The comms terminal screen flashed red, recording damage to the Deep’s internal systems from the heavy weaponry.

After catching their breath the crew decided to make their way to the loading bay and wait for Captain Valis. They found six cargo containers full of androids waiting for them. Hank opened one of the containers and the androids streamed out, trampling him before jumping through the loading bay forcefield into space. The trampling and sight of so many artificial beings preferring a life in the void to whatever fate awaited them caused panic among the crew, especially Hank and Dr. Weir, who for days had been doubting their own humanity.

Although tempted to rescue the androids, after seeing their death drive Dr. Weir and Hank decided these containers would make good distractions if things went south with Captain Valis. So, William jumped into the Auto-Tug and used his new Piloting skill to move the containers so they would be aiming at the empty space directly in front of the force field. Hank rigged the rest of his grenades to the doors to let him open them with a charge if needed.

As Hank set up the charges, the deep synthetic voice of Monarch contacted him directly via radio. Monarch immediately relayed the intimate details of Hank’s past, including how his own brother forced him to kill a business partner in a deal gone bad. Hank was emotionally destroyed by the revelation, and began to question if this memory was real or had been implanted by Monarch. Was he really human, or just another product of the evil Deep?

By the time the trap was in place, Valis arrived in a slick black Troubleshooter boarding craft. It landed right in front of the containers and he - along with six troubleshooters - came marching out of their shuttle. At this point, Hank’s unfortunate recent panic upon being overrun by androids reared its ugly head. He had rolled Death Drive, meaning he had to make a Sanity check to avoid opening fire on strangers. He failed and immediately blew the containers open and started shooting his laser cutter at the Troubleshooters.

A firefight ensued, where the crew decided subduing Hank would be harder than joining him. Huey and Dewey fled back to the control room. Everyone else started shooting and a torrent of androids flooded the loading bay, miring the Troubleshooters in a crowd and knocking several over. Dr Weir used the Auto-Tug to push around the androids and enemies and eventually lifted a container with Captain Valis inside up into the air. At this point the Troubleshooters finally made it out of the morass of suicidal androids and opened fire on TERRA. A single shot from a smart rifle was enough to obliterate her. Their death triggered a panic death spiral among the crew. A few failed Fear Saves including some critical failures and before we knew it, both Hank and Dalv lost it. Hank couldn’t handle the stress and pain of his memories and shot himself, while Dalv silently passed away with a croak in his giant slow-moving suit.

Only poor Dr. Weir remained, fighting off an acrobatic Captain Valis, who was trying to commandeer the tug. After losing control to Valis, William used one of the cargo straps to bail off the tug and safely swing down to the ground. He made a sprint for the ramp leading into the Troubleshooter ship, but in a race against the remaining Troubleshooter experts he failed. They blocked the way, a combat shotgun pointed at his face. He decided his scapel and revolver probably wouldn’t get him out of this one, so he surrendered. Captain Valis landed the tug behind him and offered a modified deal. If William gave up the artifact and threw in the logic cores of his android children companions, Valis would provide passage out of the Deep.

There was a great moment as the rest of the group waited to see what Dr. Weir’s player would do. Dr. Weir had shown great interest in saving the android children, but we had heard hints he was doing it strictly for scientific purposes, not moral ones. Here he was presented with a clear decision to show us how he really felt. He agreed to go talk to the children, saying he would go get them and return to the bay. The Troubleshooters remained and setup an ambush to grab the kids when William returned.

William found the kids trying to hack the panels in the control room. They asked if the fighting was over. Staring into their earnest, hyper-intelligent eyes, William could not betray them. He stroked his lucky rabbit foot and said, “Yes, it’s over now. Let’s go find you some new bodies.” They walked, holding hands, off into the darkness of the Deep.

A scene narrated by Dalv’s player showed the camera zooming into a crack in his opaque spacesuit helmet, smoke and gas hissing from the various tubes that kept his armor working. Inside was revealed an ancient, decrepit old man, blood dripping from his feeding tube. A mysterious ancient philosopher. Who knows how long he had been waiting for the crew in that airlock.

As a way of ending the game we thought it would be interesting to see who was an android in the end. I made the Bends rolls for all the characters and, very fittingly, it turned out only William was an infiltrator android. Seeing this result, I narrated the final scene. William, Huey, and Dewey return to HEL. Sitting at the mainframe are several figures. They swivel around on their office chairs, revealing themselves to be exact copies of Dr. Weir. “Welcome back, Doctor. We’ve been expecting you.”

My Thoughts on the Mothership System

Overall I liked this system, but it’s not my favorite system ever. I think the use of Stress and Panic really helps capture the tension of sci fi horror. I like how some things are abstracted, but there is still some crunch to get into. The Player’s Guide is nicely laid out and easy to use.

However, despite the great tools provided in the module (see below), I was surprised that I didn’t find the game extremely easy to run as a Warden (GM). I have not run any OSR games, but the degree to which this game simulates certain things relatively closely (e.g. tracking ammunition) but still leaves a lot to GM fiat, feels quite OSR to me. I know that’s a loaded term, but it seems to fit in my mind, even if I would not describe Mothership as an OSR game. The end result is that our group found ourselves struggling with a few aspects of the rules.

My Thoughts on Gradient Descent

It’s a bit tricky to separate the module from the system, since it’s my first time running both, but here are my thoughts on the module itself.

What I Would Do Differently

I might run this again for a new group. Here are my thoughts on what I would change next time around.

Would I Recommend?

Overall, yes I would definitely recommend Mothership generally and this module specifically for anyone looking for a fun and deadly sci fi horror game with a bit of crunch. I’d encourage you to consider some of the issues above and find a solution that works for your group. You can buy Gradient Descent here.