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Running Infiltration and Heist Adventures

by Mike on 4 March 2024

This article is one in a series where we look at types of adventures and examine

how we prepare them.
how we run them.
what pitfalls we might run into.
how we avoid these pitfalls.

These articles include:

Your own adventure types and how you run them may differ from mine. That's totally fine. There are many right ways to enjoy this game.

Robin Laws's book Adventure Crucible – Building Stronger Scenarios for any RPG inspired my thoughts on this topic.

Understanding Infiltration Adventures

In infiltration adventures, the characters often have significant information about their goal, the location in which they must accomplish the goal, and knowledge of the inhabitants of the location. Heists are a common form of infiltration adventure but many infiltrations involve doing something other than stealing something.

Infiltration adventures differ from dungeon crawls because the characters often know more about the location they're infiltrating and spend more time planning their approach. Goals for infiltration adventures can vary, even if how we prepare and run them remains mostly the same. These goals include:

Stealing something
Kidnapping someone
Rescuing someone
Hunting down a bad guy
Performing a magic ritual
Disrupting a magic ritual
Uncovering war plans
Recovering blackmail evidence
Uncovering evidence of a plot
Planting evidence

Preparing Infiltration Adventures

Preparing infiltration adventures focuses on the following activities:

Clarifying the goal and ensuring it's something important enough that the characters are willing to risk their lives for it.
Choosing a map. Unlike dungeon crawls, there's a good chance we'll give a copy of this map to the players.
Filling in the location with details. I like printing out a Dyson map and writing a couple of words per room or area right on the page.
Listing out inhabitants and understanding their behaviors. What are they doing when the characters aren't there? Unlike dungeon crawls, inhabitants of a location in an infiltration adventure are often more mobile.
Listing potential complications. What unknown events might shake things up? Make a list of a handful to either choose from or roll on during the infiltration.
Ensuring there are multiple paths to achieve the goal. Do they sneak in an upper window? Pretend to be servants? Delve in through the sewers below?

With that material in hand, we're ready to run our infiltration adventure.

Running Infiltration Adventures

Infiltration adventures often break down into the following phases:

Planning. Unlike other adventures, players spend a lot of time planning their infiltration.
Choosing roles. What jobs are each of the characters taking on the infiltration? Is someone acting as the "face" character? Is someone the muscle? Is someone sneaking around and spying on things from a higher floor?
Execution. This is where the real adventure begins. The characters start doing the things they planned.
Flashbacks. A concept taken from Blades in the Dark gives players an opportunity to flash back earlier in the story to set something up or acquire something they need. Inspiration or luck may be a good mechanic to allow for adjustments or additions to the party's plan.
Complications. Things never go according to plan. What changes? What complications do you throw in from your list of potential complications? Or do you roll it? Complications don't always have to go against the characters.
The climax. What happens when the characters achieve their goal? What happens if they fail or partially succeed?
The escape. How do the characters get out afterwards?

Infiltration Adventure Pitfalls

Infiltration adventures might go wrong for the following reasons:

Players spend too long planning.
The plans go out the window too early.
The characters aggro the entire location, making the job impossible to complete.
A single bad check affects too much of the outcome.
Too many complications disrupt the whole plan.
The changing situation makes it too hard to adjudicate.

Pitfall Mitigation

What can we do to help ensure these pitfalls don't crud up our fun session?

Arbitrate conversations and get the players to a consensus so the game can move forward. Ensure the players you're not pushing them down one path or leading them to utter destruction.
Keep a balance on consistency and chaos. Some things should go to plan, some things should go haywire. Don't disrupt or destroy the whole plan too early.
Use Blades-style "clocks" to escalate tension based on failed checks rather than everything going bad all at once.
Give leeway in choosing when adversaries become aware of the characters. It should take multiple failed attempts before the characters are discovered and it shouldn't chain out to every adversary in the whole location.

A Framework for Countless Adventures

The infiltration style adventure is a popular and flexible model we can use for many different adventures. Change the goal, the location, and the situation and you have something fresh every time yet still have a consistent framework around which to build your adventure.

More Sly Flourish Stuff

Last week I posted a couple of YouTube videos on High Value Prep and The Marrow Fiend – Shadowdark Gloaming Session 23 Lazy GM Prep.

Last Week's Lazy RPG Talk Show Topics

Each week I record an episode of the Lazy RPG Talk Show (also available as a podcast) in which I talk about all things in tabletop RPGs. Here are last week's topics with time stamped links to the YouTube video:

Patreon Questions and Answers

Also on the Talk Show, I answer questions from Sly Flourish Patrons. Here are last week's questions and answers:

RPG Tips

Each week I think about what I learned in my last RPG session and write them up as RPG tips. Here are this week's tips:

Write your own map key on a printed map.
For dungeons, focus on one or two word descriptions for each chamber. Save longer descriptions for complicated set-piece chambers.
Build your own binder with your favorite reference pages in it.
Stuck for an idea? Write down ten and pick the best one.
Need inspiration? Take a walk and let your mind wander.
Find a suite of tools for your prep that you love and you'll be drawn to use it.
Put dialog-friendly NPCs in the deepest dungeons – talking statues, paintings, magic items, or ghosts. Everyone wants a friend!