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Dire d20 - Mythica DarkIron |
One
of the questions I see from time to time on the subreddit for Call of Cthulhu
and the general roleplaying board, is how can you transition a group from
playing a fantasy d20 game like Dungeons and Dragons to a
horror/mystery/investigation game like Call of Cthulhu (CoC) or Delta Green
(DG)?
Since
this has also come up on the Night at the Opera discord, I decided to ask
several regular members of the Delta Green community on how to untangle this
Gordian knot. They provided the following advice.
The
Mechanical Differences
Delta Green was originally an offshoot of Call of Cthulhu, which in turn was based on
the Basic Roleplaying (BRP) system.
Explain to your players that this (Delta Green or Call of Cthulhu) is a
1d100 system, where your skills are each a percent value. Player Statistics
reflect six core abilities: Strength, Constitution, Dexterity, Intelligence,
Power, and Charisma. For normal humans (what players will be playing as),
average Statistics fall within the range of 9 to 12. In the case where a player
needs to make a test for a Statistic, say for example a Strength test to break
a door open, multiply the Statistic score times 5 (in the example, STR x5) to
get a numerical value the player must roll under on percentile dice in order to
succeed.
In
addition to Statistics, there are four Derived Attributes: Hit Points,
Willpower Points, Sanity Points, and the Breaking Point. As implied, these Derived Attributes are
dependent on the Statistics of the character.
Hit Points are representation of a character’s physical integrity, a concept
all roleplayers already understand. Willpower Points are a mix of a character’s
ability to resist mental overexertion and essentially their magic points.
Sanity
Points are different from Willpower Points. Since your players are experienced
with d20 fantasy, they may be familiar with the concept of taking psychic
damage. Sanity damage is like psychic
damage in D&D, except in CoC/DG a player’s Sanity value ranges from 0 to 99
and it is tracked with its own “health bar”, independent of Hit Points.
The
Unnatural skill, also called the Cthulhu Mythos skill in CoC, acts as a malus
to character’s maximum Sanity. The idea is the more a character understands
about the true nature of the cosmos (reflected by an increase in Unnatural/Cthulhu
Mythos skill), the less maximum Sanity they can have.
A Breaking Point is related to Sanity Points, in that when a character’s Sanity Points reaches the Breaking Point, they gain a mental disorder. The Breaking Point is then recalculated at that time, to generate a new Breaking Point of a smaller Sanity number.
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In
Delta Green, Bonds are relationships that the character actually cares about
and that anchor them into normal human society. Mechanically, Bonds serve as
ablative Sanity armor and will mitigate the Sanity damage that players take.
They serve as buffers against reaching a Breaking Point.
However,
anytime a player burns Bond points to mitigate Sanity damage, they are literally
injuring a personal relationship with someone else (usually an NPC) later
to save their own mental health now and carry on being rational in order
to conclude some mission.
In
Delta Green your characters are all doomed, and the slow degradation of their
humanity is reflected by their worsening Sanity and Bond scores.
The
Tone: Mystery, Horror, and Investigation
Tone
is setting. Most d20 fantasy settings
encourage superheroic characters and story arcs where characters continually
improve.
The
mystery, horror and investigation tone of Delta Green is radically different.
In Delta Green all the characters are doomed by the narrative. In other games
your characters are going to get better over time. In DG they degrade as they
get more experienced.
When
coming from a heroic fantasy game, change your player’s expectations as to what
they should experience in play. In a
Delta Green game player characters will not always win, and if they do not die,
they may get worse physically or mentally.
Characters are likely to die based on the design of some of the core mechanics. Combat in DG is not only lethal, but fast and lethal. At any given turn there is a chance that some other character can kill you. Let us put some numbers on that subject so that you will have an example to point out to players. The average hit points for a human character range from 10 to 12. A medium pistol that most Law Enforcement Agents carry (and that are easy to acquire in the US for most cultists) does 1d10 damage. If you are unlucky, one shot from that pistol can kill your character outright. Also keep in mind that a well-aimed car in Delta Green will absolutely erase your character from existence.
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“Treasure” from AD&D Player’s Handbook by David A. Trampier |
Having
discussed the lethality of the setting, a word about the murderhobo
mentality that is sometimes observed among players of d20 fantasy games. I will define murderhobo behavior as a player
attempting to use combat, violence or intimidation on every situation or NPC
they are presented with to advance the plot. This activity breaks believability
in modern games and damages the tone of mystery, horror, and investigation
games.
To
deal with this problem, the Night at the Opera hivemind suggested the following
points:
1. Remind the player that Delta Green is set in the present day. The setting is the real world and there are real world consequences to actions. As a corollary, if the player shoots an NPC in public, remind them that everyone has a phone.
2. Most importantly, gently remind the player that the purpose of the game is for the group to have fun, and actions taken by all players (and the Game Master is a player too!) should enhance the fun of the group. Do not take actions to have fun at expense of other people.
Another
consideration about the tone is that players in a horror game should be ready
to be vulnerable. Since Delta Green characters are at risk of severe physical
and psychological harm, the players need to be open to experiencing and
roleplaying those situations and communicate their limits with their fellow
players and the Game Master.
One
last piece of advice was, since Delta Green usually has elements of mystery and
investigation in the tone, players should take notes to keep track of
information. A good idea is to share a
Google Doc of notes with all the other players. Whomever is the least-active in
the current scene should write down the clues found.
We hope these suggestions help Game Masters smoothly introduce new players to Delta Green and Call of Cthulhu, and help everyone at the table have more fun.
Acknowledgements
I
want to thank the following people from the Night at the Opera discord for
ideas and review of this post: Bird Bailey, Sammy J, Fee Fi Fo Fin, Frahnk, and
magnificentophat.
Update: 6/14/25
Session
Zero
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5th Edition Dungeon Master's Screen by Hydro74, image by AugusteBlanqui |
A
Session Zero is a precursor session for a roleplaying group where ground rules
are discussed and the GM introduces the tone and objectives of the game or
campaign. Generally, this is the session that characters are made with whatever
prerequisites are required for the initial adventures. For example, you might need a healer in the
party if you are running a dungeon crawl, or a detective type character if you
are running a police procedural investigation.
The
Session Zero is not a new concept. As I recall, I was first exposed to the term
when I was reading the Dresden Files Fate game around 2010, and some internet
research on rpg.net suggests the term was in use as early as 2003. Back in the AD&D era, an informal version
of Session Zero was just called a conversation with the DM.
In
either case, communication of player and GM expectations is the point of the
matter.
In a Delta Green game, a Session Zero is the perfect opportunity to discuss the tone and Game Master expectations with players. Since this is likely their first time with a new system, the GM can introduce the idea of horror and mystery in a game, and what the GM expects of the players; whether it be certain skills needed to not fail at the mechanics of the adventure, or character behavior during the investigation. This meeting should start everyone on board with a clean slate, with the understanding that they will be playing something different than d20 Fantasy.
Recommended
Beginning Scenarios, Delta Green
Since
this blogpost is focused on players and Game Masters new to Delta Green, here
are some suggestions for free adventures that are focused on introducing the
game to a new group. The question of
“what beginner adventures are right for my group” comes up quite often on the
Night at the Opera discord, and everyone has their favorites; these are just
some of mine. I will explain the utility of each adventure as I see it after
they are introduced. As such some adventure spoilers will be discussed
to players, please avert your eyes from this section.
First
and most venerable, I must start by introducing the official scenario Last
Things Last. Much has been written
about this adventure around the internet, so I will just say that it is short,
introduces investigative work at the beginning in one contained location, gives
the players room to breathe and roleplay, and usually introduces combat at the
end. Last Things Last is in the free starter rulebook Delta Green: Need to Know.
The Signal Smugglers by mellonbread. A
perennial favorite, this scenario does the brilliant thing of having the
players smash cut to roleplay police (who are not their characters) outside of
an apartment. Combat is introduced and chaos ensues. However, since this combat
is an introductory scene not related to the players’ actual characters, the GM
can introduce the fast and lethal combat of Delta Green without consequences
for the player characters. After the initial sequence, an investigation is
introduced with antagonists that can actually be negotiated with.
Enemy of the Tribes by David Tormsen. This was the first adventure I played in, in my current DG campaign. I have written a partial after-action report about the experience here. The adventure starts out with a crime scene and then blossoms out to a more general investigation and tracking down of other potential victims. The monstrous antagonists can be used as combat or eerie encounters at any point during the investigation, and likely make an appearance during the finale. Some work is required to create combat encounters appropriate for your party of players.
The Button by Will Roy. This adventure is
primarily a roleplaying event with some investigation around an enigma that is
like intellectual quicksand. It is a
great way to introduce the Mythos as not just unspeakable alien gods and rabid
cultists. There is an option to include
a Mythos gribbly at the end if the Game Master desires.
The Midnight Sun by Will Roy. This adventure was my first reintroduction to Delta Green after a years long hiatus. It works really well with two players with complementary skill sets. Though in the Delta Green world, this is actually an M-EPIC scenario. M-EPIC is the Canadian mirror to the US Delta Green anti-Unnatural program. For more details about M-EPIC check the Delta Green Handler’s Guide, specifically page 271.
To
make this a Delta Green beginning scenario, simply change the location from the
Yukon to somewhere in Alaska. A Game
Master may also need to change the origin of the NPC McBee from an “American”
to someone who simply is not familiar with the freezing wilderness far from
civilization. The Mythos gribbly
presents an interesting roleplaying experience, sort of similar to the end of
Last Things Last (above). I wrote up a
semi-novelized after-action report of my experience with The Midnight Sun,here.
Take the A-Train by Bird Baliey. A
great introductory scenario that can be dropped into a campaign to interrupt a
chase scene (the player characters need to take the subway) or played by
itself. Think of this game as a stage
play. It is in one location with a fixed
number of characters and a common problem. Great opportunity for roleplaying
under increasing tension.
The (Un)Natural Man by Bird Baliey. A domestic disturbance that leans heavily on
investigation, roleplaying and interpersonal skills to deal with adversarial
NPCs. The finale may involve conflict
with a Mythos gribbly or may be very dark. If the Game Master has a streak of
dark humor, this is the scenario to play to exercise that inclination.
Five Alarm Firefight by Bird Baliey. A
Delta Green adventure designed to introduce new players to the nuances,
dangers, and mechanics of combat as well as rules like exhaustion. Puts the
players into civilian law enforcement or rescue roles with no prior knowledge
of the occult needed. They will get plenty of that if they survive. This
scenario is most analogous to a dungeon crawl because the player characters
will investigate an apartment building room by room with investigative skills
to attempt to find clues, and interpersonal skills to deal with NPCs.
Ultimately both tactics will be fruitful for unraveling the mystery.
Having
said that, the structure of the adventure is not a linear railroad. There are
multiple instances where there are alternate routes to take, even if they all
end in a central fixed climactic scene. The danger from humans with firearms
will be on display. Pregenerated
characters are included for the adventure.
My
understanding is that Five Alarm Firefight will be updated soon, so check the
link on occasion!
Recommended
Beginning Scenarios, Call of Cthulhu
I was
originally the always-GM for my Call of Cthulhu group in the late 90s. I have
not kept up with the plethora of adventures for the system, but I do remember
the classic adventure The Haunting. And I remember it fondly because one
of my investigator players never made it up the basement stairs under his own
power. Thanks to a Series of Unfortunate Events (just read The Haunting,
seriously), his companion had to drag his physically knocked out ass upstairs
twice to save his life. Good times were
had by all.
The
Haunting provides a series of floating encounters that can be plugged into the
adventure at the GM’s discretion. It is
a classic for a reason and many others have opined far better than myself all
over the internet.
The Author by MrNightmares. I would be remiss if I did not shill my own
Call of Cthulhu adventure. Made for one
or two players at maximum, the adventure features a mysterious disappearance
and a timeline of events that ratchets up the tension as things get worse until
there is a potentially fatal endgame if the players do not put the clues
together in time. The weakness in this adventure is that it can hinge on the
players finding and reciting a certain incantation to get the antagonist’s
attention, so Game Masters may need to work on that. Features one antagonist that may not be all
that terrifying to confront depending on how the players proceed. Could link this adventure into further
adventures against a Cthulhu cult.
Want
more adventure recommendations or just more advice on how to start playing
Delta Green? Check out Sammy J’s Beginner’s Guide here. It is worth your time.