Planet Mercenary: Delving Dungeons

So, I am finally on top of my various projects enough that I can write a little bit about Planet Mercenary. I am so excited for this game and I’ve been giving it a lot of thought. One of the things that will be very different in PM from other games is dungeon crawls. Will they be possible? How do you write them? Won’t they have ways around doing the dungeon and just straight the prize?

I have no idea. Let’s find out.

Dungeoncrawls are an RPG staple. Many players are familiar with opening a door, seeing a 30ft corridor, and moving to the end of that to interact with the door on the far side. Rooms with a limited number of exits, doors with traps, monsters that have moved into these ruinous places, and, most importantly, some vast treasure at the end. Dungeons are also notable in that they play out the same way, mostly, no matter the part. There are these monsters to fight, these doors to deal with, no exceptions. Letting people out into the fictional world with their Social Skill shenanigans quickly makes for a vastly different subset of the game, as player imagination and die rolls can make the NPCs do an almost infinite number of things. Well designed, popular dungeons create an experience they can share, comparing how they did against the Red Room with their parties.

So, dungeons are cool and desirable. Check. It’s also good to note that while our mental picture of a dungeon is a slimy dark stone corridor heading into the bowels of the earth, it could easily be a mob owned network of tunnels in an asteroid named Paris, or a deck to deck search of Captain Picard in an otherwise abandoned Enterprise. Dungeons transcend genre.

What are the issues we’re going to have for making them in PM? Here’s what I can think of.

  1. Why are we here?
  2. Removing the Warship (and other technical cheats)
  3. Intentionally designed for theater of the mind, or “Do we need a map?”
  4. Ranged weapons vs Melee
  5. What can you fight in a PM dungeon?
  6. How do traps work?

1. Why are we here?

The first consideration for our players and Game Chiefs is why is the company going into some rank catacombs? And this may be the easiest of all of our questions to answer. Our players are going in there for one thing: profit. In games like D&D, players may delve a dungeon to save the world, but not our mercenaries. Saving the world has a price tag.

Here is a quick sampling of dungeon plots that I came up with rather quickly while writing this article. Feel free to merge, modify, mutilate, or just ignore these to make them work at your table. Hopefully they’ll invoke a lot of cool ideas.

  1. Capture the Flag: There is a macguffin in the dungeon that’s being actively protected. A TAD that needs destroyed by a strike team. A oerson who really needs to become a hostage or a bounty. A hostage that you’re being paid to recover. Alive, naturally. A safe that contains the plans for some wicked sweet superweapon.
  2. Hunt the Wumpus: There is some foe or beastie in an otherwise empty enclosure. The may be some traps that got set by our quarry. Also, he probably knows the terrain a lot better than we do, so we might be tricked into dangerous terrain and fights with local fauna on our pursuit to smoke him out.
  3. There’s Gold in Them Hills: It’s been a local legend for ages. Deep inside the ruins of old Fort Murder-Death, an impossibly large treasure is down there. Of course, no one who has gone down there has ever come out. You’ll be fine, though.
  4. Trapped like Rats!!: Through a cave in, a bad teraport, a wicked crash, we seem to be stuck deep in the earth. The only way out seems to be to traverse these caves carved with all sorts of ancient runes and stuff.
  5. Find and secure a passage: You’re not the main army. That’s someone else’s job. You’ve been hired to quietly find a path through the Catacombs of Quantum Doom, mark it, secure it, and open the gates so the main army can catch the defenders with their trousers around their ankles.
  6. Quick! In here!: Maybe this is your base, maybe this is your fall back location, or maybe you hadn’t planned on delving a dungeon, but it seemed like a great way to get away from whatever you were running from. So, in addition to whatever is in here, you’re being pursued by someone. Rivals or the police, or maybe assassins. Better leave some clay-mores point to the enemy behind and keep running.

So there are a lot of good reasons to be in a dungeon. And when you think about it, a lot of scenes we can have in our game may just be a dungeon that’s only a room or two long. Ideally, this article will help us be able to have larger, sprawling dungeons, while still fitting in the PM style.

2. Take away the warship (and other toys)

You see this in Doctor Who. You see it in Star Trek. There’s probably other good examples. Players have a lot of cool toys, especially in Planet Mercenary. Dungeons aren’t scary if it’s easy to get in and out of a place. In fact, it makes them pointless. Difficulty of access is probably a good slice of rubric for what makes a dungeon. So what toys do we need to take away?

First, Teraports. The biggest Aha! of PM comes with a built in off switch. If you don’t want the players teraporting, then there is a TAD in place. It could be the residents of the dungeon, keeping people like you out. It could be a planet wide TAD, as is common in a lot of places that can afford it, as teraporting is a nasty trick that places like banks and the like tend to dislike. It could be a natural TAD-like effect. Some hyper magnetic stone or other technobabble. You also need to have good targeting data for a teraport insertion. If someone is jamming the hypernet, it may be hard to get a good place to land. Or maybe they’re spoofing the hypernet, setting your strike team up to suddenly be stranded deep behind enemy lines in the dungeon, as per number 4 above. This is should be pretty easy to resolve.

Second, The Warship. In my first (and, annoyingly, only) PM game, I had a bit of a dungeon prepared and one of my players wanted to know if they you use the ship’s weapons to bore a hole in the mountain to get at the hostage. I gave a technobabbly no, as I was playing with an incomplete set of the rules and I couldn’t improv without going seriously off the rails. Now, though, with an (almost) finished set of rules, I would smile evilly and say, “sure, if you want.” See, most planetary forces look poorly on a no-name mercenary group opening fire on the planet. Threat of legislation or pursuit by the boys in blue (or whatever color the sophonts of your local planet constabulary wears) should be able to dissuade them. And if not, well, suddenly, you get to run a different game altogether. Set your dungeon aside. Tonight’s game is “running from the cops” otherwise known as “why we don’t use warships on planet.”

You can also use things like anti-air defenses or the like, to get people off the ship. Or if they’re stranded from their ship, perhaps by a bad teraport or a job gone south, cutting off contact with the ship can work wonders. You don’t even have to jam, if it’s clear that the bad guys have done some nodephreaking, so they can find where you are when you try to call for back up.

Really, the mission itself may have its reasons and method to keep the warship away built right into it’s bones.

Third, Flight. It’s kind of a higher tier issue, but characters can develop a few ways to fly- armor, vehicles, etc. Sometimes, this abillity to easily move in three dimensions can circumvent your dungeon design. And, unlike the other two points, I believe that’s a good thing. Letting people fly past you’re super deep pit makes them feel awesome for investing in flight for their characters.

Of course, if you really want to discourage flyers, you can keep in mind a common nickname for flying soldiers.

3. Dungeons in the Theater of the Mind or “Do I need a Map?”

Part of the design of PM makes the standard dungeons with its five foot squares look like it won’t work at all. There are no gridded battles, which is what most dungeons work best as. So that puts a lot more work into the hand of the GCs.

So there are three ways I can see to prepare a dungeon for PM. First, the GC prepares a map and reveals it room by room to the players, effectively abandoning theater of the mind for clear positioning. Second, the GC prepares a map for his own reference, telling the players about the layout, using theater of the mind with a cheat sheet. Third, to have a list of rooms, perhaps in little bubbles with arrows drawn, the absolute bare minimum needed to run a dungeon.

Okay, there is a fourth, barer minimum, of having no notes and making it up as you go. While this is technically doable, it won’t lend itself to good dungeon design. It’ll be harder to make clever connecting passages, to tie the space together, to make it seem like a real place. You can get lucky, of course. And, ideally, reading the rest of this article will give you some tools to make it as easy as you’ll get. This undesirable fourth option should be in your back pocket as a GC, if the party starts going in odd directions. It gives you something the party can interface with as you frantically tear out your old plot and write a new one.

So, starting in reverse order, let’s look at a flow chart style dungeon.


I mocked this up in mere minutes. Really simple. I could use this to run almost anything. There is really only one thing that needs to be explained and that’s the awkwardly designed one way passages. I couldn’t think of anything better.

So the players arrive at the enterance. You set the scene, maybe have a locked or sealed door. Then they find the antechamber, which has a trap that will send them down the slime slide into the sliem room. Too slick to climb back up, so they’ll have to pick one of the two doors here, after maybe fighting some disgusting monsters. The Stone guardian room have some large statues that might be animate. Or not. But there’s probably a fight in here. Good job in flanking the people paying attention to the antechamber door. From here, you head to a room where the floor has mostly given away. Be clever, or fall, although I think there is some water below. When they fall, taking some damage, loosing some equipment, but smelling of slime no more, they find a passage up to the big boss fight in front of the treasure door.

As you can see, there’s no one true path through the dungeon, and there isn’t any dead ends, where failure ends everything. Of course, that’s just how I designed this. And in being super vague with what’s in each room, you’re free to design whatever the heck you need for your table, designing whatever foes or traps you want.

Honestly, if you are doing method 4, you’re basically doing this method here, just with little time between figuring out the cool name for the room and describing it to players.

Some interesting points of note, that you can use or not. First, most rooms here have two options of where to go and at least one of those moves the party forward. The only rooms that don’t are the entrance and the goal. And you could easily attach those to other passages, spawning a really large dungeon.

Let’s look at this a little more organized, for method 2.


As you can see, this version of the map is designed identically to the previous one. There isn’t the obvious marks saying how people wind up in the slime room or the dark water. That isn’t really a bad thing, as you can then use those rooms for more than a simple destination. This map would need to have a key with it, a short description of each room, what’s in it, as well as non-obvious connections (like the slime trap). I also left the exact details of each room out. Figuring out exactly what the Stone Guardians are, or the exact placement of the Really x2 Deep Pit is up to the GC as he’s running the game.

I also didn’t key distance, even though I arduously drew the grid instead of using the tools I had to auto generate it. PM doesn’t list distances beyond short, medium and long. Most rooms will be medium length, maybe the far end of short.

The biggest part of method 2 is knowing these distances and having all of the adventure keyed up, instead of seat of the pants.

Method 1 is to take that map above and give it to players, whether slowly or all at once. And maybe if the dungeon has filed it’s blueprints with the local bureaucracy, its a thing they could get right away. With some social or Compter skills. he lead up can be half the adventure.

Personally, I’m more likely to use method 3, as it’s really quick and easy. I hate doing more work than I need to, especially since it’s really easy in PM for things to not go as planned. But each of the methods has their own place. It’s good to know what tricks you can use to change it up.

4. Melee vs Ranged

One of the simplest, yet profound changes in PM from D&D is tat all characters suddenly specialize in ranged weapons. This means that if they see foes from a distance, unless they have a good reason not to, they will deal with them at said range. This isn’t really a problem, per se, it’s just something we have to keep in mind as we’re designing things.

Interrupting sight lines is the best way of making ranged abilities less powerful. Oh hey look. Our definition of dungeon puts us in rooms with walls, floors, ceilings, the whole kit and caboodle. Turns in the passage ways, twists and turns in the cave, even a bunch of stuff piled up in the large room you’re using for your fire fight, plenty of things can limit ranged combat. Of course, people want to attack from a distance, as getting up close and personal can result in sharp an pointy things in your person, which most sophonts list as undesirable. So forcing players into melee and then twisting the knife by making their foes good at melee is a bit of a jerk move.

The other classic inhibitor of range is light. As far as I can tell, there aren’t specific rules for darkness. I assume its designed for the GC to set a higher Target Number if you’re trying to do something in the dark with adding some light. It’s the future. Everyone should have some way of getting light. Of course, the only light source in a dark room sounds suspiciously like a target.

Fog or mist or something can also work, although you may want to foreshadow it when they’re landing on the planet. Especially if its going to be poisonous. Now, if someone triggers a trap and the room is flooding with poisonous gas, well, that’s on their heads.

It’s probably worth noting that if you’re planning on doing some deep megadungeon, PM doesn’t have you tracking ammo or rations, except in special circumstances. Make sure you know what you’re doing before messing with that aspect of the game.

5. What can you fight in Planet Mercenary dungeons?

Nothing is as important in an RPG as having foes to mow down. One of the cool things about dungeons is they’re flexible enough to fit almost any of the mooks already listed in the appropriate places in the PM book. It depends on the job your on as to who the foe is. But here is a handful of other M3s (Mooks, Mobs, and Monsters) you can use for your dungeons. These are designed for that quick dungeon I made, but use them for whatever. I have no idea how strong these are, compared to other M3s. Use with caution, as I haven’t play tested these at all.

  1. Goober Slime Blob Swarm(Mob. 60 individuals, 10 squads)
    1. Attack: 3d6+3 (melee only)
    2. Damage: 0d6
    3. Defense: 10
    4. Reduction: 1
    5. Health: 2 per unit
    6. Special: On a hit, the goober slime blobs surround the target, holding it immobile to the ground, requiring a TN 20 Athletics to break free. A goober slime swarm can deal 1d6 damage that ignores reduction as they excrete a noxious acid that seeps through available cracks.
    7. “Goober” slime blobs have no relation to the well known non-lethal ammunition. They’re similar in the fact that they will immobilize you just as easily, but the comparison falls apart as they start digesting you while you’re still in your armor, something all goober manufacturers universally claim is a feature intentionally absent from their product.
  2. Stone Guardian (Individual)
    1. Attack: 3d6+8 (melee only)
    2. Damage: 3d6
    3. Defense: 18
    4. Reduction: 10
    5. Health: 20
    6. Special: May only make one attack per round. TN 20 Perception to identify a motionless stone guardian as anything that could move.
    7. The stone guardian appears to be a 10 foot tall stone statue. This is by design. When it notices something intruding on the area that it is supposed to be guarding, it will attack, swinging it’s massive stone fists. There may be some kind of circuitry underneath the rocky exterior. Use breacher rounds to know for sure. Some kind of Insight skill check might let you discern what the guardian recognizes as marking individuals as supposed to be there.
  3. “Salty” Peter Black, disgruntled Archeologist (Individual)
    1. Attack: 3d6+5
    2. Damage 2d6+2
    3. Defense: 15
    4. Reduction: 3
    5. Health: 12
    6. Special: Limited Flight, Active Camouflage.
    7. Peter Black, “Salty” to the people who talk about him behind his back, used to be a dungeon delver himself, before he was stinted by too many universities. So he went rogue, doing freelance archeology, often on the shady side of the law. He’s not in it for the history or the knowledge anymore- he’s in it for the money.
  4. Nani-Zombie Horde (Mooks, 6-12, 1 squad)
    1. Attack: 3d6+1 (melee only)
    2. Damage: 1d6
    3. Defense: 11
    4. Reduction: 20
    5. Health: 3 per unit
    6. Special: Any character that dies in a room these are in rises as a Nani-wraith 2 rounds later
    7. Everyone knows there’s no such thing as the undead. Except, of course, when you take a dollop of nanis and let them make a meat suit of a recently (or less so) deceased corpse.  Then it starts getting all horror movie-esque. Sure, you can hit them easy, but unless you blew them to shreds with some heavy ordinance, they’ll keep coming. And the whole time, they’re infecting the air with nanites. Nothing that will cause you harm, but if something dies in their clouds, you’ll see your dear friends again- rising with a dead look in their eyes, thier weapon trained towards you
  5. Nani-wraith (Individual)
    1. Attack: 3d6+4
    2. Damage: Special
    3. Defense: Special
    4. Reduction: 20
    5. Health: 15
    6. Special: A nani-wraith is a dead character come back to life. It uses their armor, and weapons, with little sense of self preservation.
    7. Once the nani-zombies descend, dead characters, players or grunts, come back as a nani-wraith. Hopefully, you had time to loot the body, stripping it of weapons and things like grenades. Otherwise, you may be in for a tough time of it. Once they’ve died again, however, they’ll be down for good. If only that wasn’t hard both psychologically and physically.
  6. Giant Rat (Mooks, 3-4 individuals, 1 squad)
    1. Attack: 3d6+3
    2. Damage: 2d6+1 (melee only)
    3. Defense: 13
    4. Reduction: 2
    5. Health: 4 per unit
    6. Special: Can only make melee attacks
    7. Every dungeon has to have some giant rats, right? even when it doesn’t make sense. These are a bit nimble and dodge attacks easily, but they’re not that tough.

Mkay. So there’s some things to fight, right out of my noggin. Making M3s is both deceptively easy and tricky. I have no idea what the numbers mean, which makes them shakey when it comes to them being good numbers, but they were super easy to make because of it. I need to get some games going, to figure out what’s what.

6. It’s a trap!

One of the big classic things about dungeons is they tend to be well defended with traps. In my perusal of the PM manual, I didn’t see anything along trap lines. It’s mentioned a few times, but not with any rules involved. So now I get to make up a bunch of reasonable sounding rulings on how to runs some traps in your PM games. Huzzah!

First, there are two kinds of traps. The first is more like a really stupid enemy- it can make an attack roll under super specific circumstances and it’s attack is processed exactly like an attack. So much so that we will call these an “Attack Trap,” possibly shortening it to AT or A-trap. Let’s build one, real quick.

  1. Needle Lock Trap (Targets 1, embedded in door)
    1. Attack: 3d6+6
    2. Damage: 2d6+2
    3. Skills: TN 20 Perception to notice, TN 20 Mechanics to disable
    4. Special: Attacks target attempting Larceny on door. Triggers if Larceny check to unlock is under 20. Attack ignores reduction.

So you’ll notice it looks a lot like how I typed up the M3 stats, although I’ve replaced it’s defenses with a “Skills” category. That’s because there is little that guns do to fight off a needle trap. Sure, you  can blast the door, but if you’re blasting the door, you don’t need traps. The party can get melt their way to the destination. You don’t need to worry about locks in that scenario either. A-traps are complications for soponts trying to do things the quiet and sneaky way, with some quiet and sneaky defense. Let’s build another

  1. Lightening Floor Trap (Targets 5, embedded in floor)
    1. Attack 3d6+10
    2. Damage: 3d6
    3. Skills: TN 15 Perception to notice, TN 25 Mechanics to disable
    4. Special: Attacks up to 5 targets standing on floor. Triggers if a member of the party fails a Stealth Check (TN 15) to pass by the pressure plate without stepping on it.

So that’s what the other end of the A-trap spectrum looks like. The lightening floor trap is easier to recognize, as you can see the copper wires or whatever exposed on the floor as part of it. Disabling it is trickier, however, as it has more redundancy and the controls are way over there.

Skill Traps,  (ST or S-traps) are the second category. Instead of making an attack against the characters, once triggered the characters have to succeed on a specific check or suffer consequences. Pretty simple. Let’s build some!

  1. Collapsing Floor
    1. Trigger: Weight is put on the collapsing floor
    2. Notice: Perception TN 20, Engineering TN 15
    3. Avoidance Skill Check: TN 20 Athletics check to jump to safety
    4. Consequence: Character falls to whatever’s below
  2. Collapsing Floor (with spikes)
    1. Trigger: Weight is put on the collapsing floor
    2. Notice: Perception TN 20, Engineering TN 15
    3. Avoidance Skill Check: TN 20 Athletics check to jump to safety
    4. Consequence: Character falls to whatever’s below. Turns out its spikes. 2d6 damage from sharp pointy trap.
  3. Giant Parody Rock
    1. Trigger: Idol sensor detects weight change
    2. Notice: Perception TN 25
    3. Avoidance Skill Check: Stealth 25 to find an alcove to let the rock roll past, Athletics TN 20 (Pursuit, running) to out run the rock.
    4. Consequence: Rock will roll all the way back to the entrance. The character’s Athletics Check will let you know how far they make it before being crushed by the rock for 4d6+3 damage.
  4. Sleepy go bye-bye gas trap
    1. Trigger: Wrong lever is pulled trying to open the door.
    2. Notice:Perception TN 15
    3. Avoidance Skill Check: Endurance TN 20 to resist effects. Any breathing apparatus lets you make this check without rolling
    4. Consequences: Creatures who fail their Endurance check are unconscious for a bit.
  5. Motion Sensitive Alarm
    1. Trigger: Sense movement in sensor range.
    2. Notice: Perception TN 10
    3. Avoidance Skill Check: Stealth TN 25 to move in its sight without looking like you’re moving.
    4. Consequences: That loud beeping means someone knows you’re here. Better get cracking.

So that’s how I wrote those up. I’m not exactly happy with them. Traps are a bit of a complicated thing and can end up being a crazy combination of effects, skills, role play, and a slew of other things. So trying to shove that all in a 4 item list never sits well with me. But as long as you know to take these only as guidelines for your game, not gospel, you’ll do fine.

7. In conclusion

It turns out, dungeons can be a compelling part of story telling in Planet Mercenary, just like in other RPGs. It’s easy enough to make maps, even if you don’t hand them to players. While there are some things players can do to get around doing the dungeon crawl, there are ways GCs can react. And traps and monsters seem easy enough to build.

I hope this article helps make running a dungeon in you PM game a bit easier. Please tell me below if it did. And if you have anything else I ought to write about, please let me know.


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  1. Well done!

    One scenario not listed: boarding an enemy ship. This is a staple of space opera, and if the ship belongs to someone who is genuinely alien in the way they think and build, the ship interiors will be full of surprises for the players.

    The boarding operation automatically places limitations on players:
    1) We’re boarding because we want something INTACT. No more STS or heavy-infantry weapons until we get back out.
    2) Teraport Area Denial is a standard feature on any decent vessel, and it’s going to be powered in ways that make it difficult to cleanly disable from the outside. Indeed, it will likely be distributed, with overlapping fields, ensuring that there’s no single off-switch that throws the crawl into easy mode.
    3) If players want to venture off the edges of the map you’ve created, they are either a) in immediate need of good environment suits, or b) now attempting a very dangerous alt-version of the dungeon crawl known as the hull crawl. And for b) to work well, they’ll need to find a way back IN, which is something that you, as the Game Chief, are in control of.
    4) STAR WARS: THE FORCE AWAKENS gives you a plot template for a truly twisty adventure – multiple factions boarding the ship, the ship is carrying dangerous live cargo which has gotten loose, and the MacGuffin is “retrieve your own ship from the clutches of this one.” Every good Game Chief should be familiar with John Cage’s famous aphorism: “well stolen is half-composed.”

    Your work above is outstanding, Matt. I look forward to reading the debriefings from your players. 🙂

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