Voyage Through The Enemy Within

Charting the River Reik, A GM’s Voyage Through The Enemy Within Part I

Who am I?

I’ve been playing tabletop RPGs for many years, but most of the games I played were more focused on “roll-playing” than “role-playing.” That is to say, instead of embodying a believable character and living out a story, our sessions were more like “we gather with friends, roll some dice, and fight dragons.” For most of those years, I played Pathfinder (1e), and I learned a lot about how systems work, what mechanics-heavy games look like, and how to position and move most effectively on a battle map.

At some point, I realized that what I was doing wasn’t really playing an RPG – it was more like playing a board game, with only brief moments of actual roleplay. As a result, I started searching for more narrative-driven games.

Lately, I’ve been asking myself: What exactly is this hobby we call tabletop RPGs? What do we classify as a real RPG? Is there a “better” way to do it? These are subjective questions – much like how we evaluate quality in art or literature – but I believe it’s possible to form an idea of what makes an RPG deeper, more intellectual, or more meaningful. So, I began to focus on questions like these. I reflected on my own RPG experiences and studied those of others, considering what each game contributed to me and which sessions felt like time well spent. In short, I’ve been on a quest to answer questions like: What is an RPG? In which shapes or forms it can be enjoyed? What different styles are there?

Why Enemy Within?

It all started with a simple question: What makes a good tabletop RPG adventure? How should one be written?
From there, I began looking into the most highly recommended and widely praised published modules – and Enemy Within was one of the names that kept coming up. Released in the late 1980s, this campaign has been celebrated for decades. But why? Why has a scenario that’s nearly 40 years old and one of the first examples of a published fantasy campaign remained so important? Why did it get revised for later editions of Warhammer? What did it do right – and where did it fall short?

I began this project to explore those questions and to challenge myself with a different GMing style than I was used to.

How Much Work Is It to Prepare Enemy Within?

When I decided to run Enemy Within, I wanted to preserve that signature Warhammer atmosphere – grim, oppressive, and miserable – but without getting bogged down in the system’s complexity. At the time, my knowledge of both the Warhammer setting and its rules was mostly secondhand.

As with any published campaign, it was highly recommended to read the entire story from beginning to end before starting. That meant a lot of reading for me. The full series includes five main adventure books, each accompanied by a companion volume – ten books in total. On top of that, there’s the core rulebook, which I had to read and learn thoroughly. And once all that was done, I still had to figure out how I actually wanted to run the game and which rules I would use or ignore.

Of course, simply reading the books isn’t enough – there’s also session prep. Luckily, that’s not something you do all at once; it’s a process that unfolds week by week.

My First Impressions

With the recent additions and revisions, the story feels impressively rich and expansive. It’s clear that the writers assumed many readers would have already played through the original version of the campaign. Scattered throughout the books are numerous sidebars suggesting adjustments “for returning players” or “for players who already know certain meta-informations.”
While I personally think prior experience with the original version isn’t particularly important when writing or running this campaign, these adjustments undoubtedly help make each Enemy Within game feel unique. I plan to incorporate some of them into my own run.

I also appreciated the addition of the companion books – they offload much of the setting material, leaving the main books to focus almost entirely on story.

So far, one of the most impressive aspects of the campaign is how NPCs who seemed minor or irrelevant early on return in later books – having continued to act off-screen in the intervening time. Reading ahead and suddenly recognizing familiar names gave me a strong sense of being part of a living world.

If I had to name the weakest part of the story so far, it would be the character hooks – the way the player characters are connected to the story. Unless the players or GM come up with their own motivations, there are usually only one or two baked-in reasons for getting involved in the plot. This becomes especially problematic between chapters and at the very beginning of the campaign. Without personalized hooks, it’s hard to answer the question: “Why are these characters even going there?”

In some cases, the suggested motivations are so minor or easy to miss that I had to flip back and forth between the beginning of one book and the end of the previous one just to remember how the story justified a transition.

Another issue I noticed is the presence of “railroading.” Despite offering lots of options and branching paths, certain key moments give players very little actual agency. If specific clues are missed or certain decisions aren’t made, the entire story can stall. Often the players are expected to pursue one or two specific leads – but the story doesn’t always provide strong reasons for their characters to do so. In that sense, the campaign feels like a river: broad and open in some parts, narrow and constricting in others, occasionally forcing the party through a needle’s eye.

Many online reviews echo these concerns and offer suggestions for smoothing out rough patches. I plan to implement some of that advice. For my group, I’ve asked that the characters know each other in advance and have at least some personal connection – that way, they’ll start with a more cohesive reason to travel together.

Warhammer System and My Mechanical Preferences

Warhammer uses a d100 system. While character creation and progression can seem difficult and complex at first, it becomes clear that it’s not so bad once you start actually getting into it. Still, the rest of the system involves quite a bit of math. Since I wanted my game to be more narrative-focused, I decided to set aside a large part of the mechanics. That said, I’d like to explain which parts of the system I’ve kept and which I’ve skipped.

First and foremost, I didn’t want my players to worry about learning the Success Level (SL) system or calculating how many SLs they gained or lost with every roll. While pausing to check the dice or consult the character sheet isn’t especially complicated, and it gets faster with practice, but there were players in my group who would have trouble doing it quickly. And Warhammer has this particular quirk: even if not for every roll, most rolls include difficulty modifiers ranging from –50% to +60%. Some talents also grant additional SLs under certain conditions. These little intricacies create a cumulative layer of complexity. It means players often need to do multiple calculations per roll and cross-reference abilities that could influence the outcome.

People used to D20 or D&D systems might find these complaints exaggerated. After all, it’s just simple math and being familiar with your sheet. I get that – but each time the system intrudes, the players shift focus from imagining the game world to analyzing dice, numbers, and rules. And if you think about it, you’ll realize how often players spend over 30 seconds on a single roll. I’m faster than most, but even I sometimes go over a minute when I’m calculating all my various bonuses. Sure, once the system is fully internalized, these delays shrink – but they never disappear entirely.

I want my players to interact with the game world as their characters, not as players who try to do the thing that’ll give them the best odds. So I’ll be keeping a copy of their character sheets myself and simply asking them to tell me the numbers they roll.

Now let’s talk about combat – a part that tends to take up a lot of game time. I plan to run all combats using the “Theatre of the Mind” method. The reason is simple: tactical maps may help with positioning, but they reduce cinematic fight scenes into dry board game mechanics.

Let’s start with the Advantage system. Advantage is a number tracked separately for each character. It’s gained in various situations – such as winning an opposed test, damaging an enemy, or taking some tactically clever action – and resets under certain conditions. Characters receive +10% to tests for each point of Advantage, and some actions even allow spending it for extra effects. In short, Advantage is powerful, and since it’s tracked per character, it becomes almost like a mini-game on its own. To avoid it taking over the game, the rules suggest placing limits. I went a step further: instead of tracking it individually, I decided to use a shared system for the whole group. Either the party or their enemies have the Advantage at a given time, and it’s capped at a maximum of +2 or –2. This way, the maximum gap between both sides is just 40%.

Now, onto the action system. Personally, I’m tired of the “move with my move action, attack or cast a spell with my standard action” structure. In systems where actions are more varied and flavorful, this flow can work — but Warhammer doesn’t really offer that. When it’s your turn, you don’t have many options unless you’re especially creative or happen to be a priest or wizard. Most of the time, your only real option is to swing your weapon.

Sure, you can attempt things like tripping someone or aiming for a specific body part, but doing so imposes penalties to hit and increases the chance of getting hit back – unless you have specific talents for it. This creates an illusion of choice: the game makes it seem like there are lots of options, but in reality, most choices aren’t viable. Because of that, I’ve decided to treat the action system as if it didn’t exist.

In the end, I want my players to create characters and roleplay them. They’ll describe how someone in this grim world would think and act. When necessary, they’ll roll dice and tell me the result, and I’ll describe what happens. From the players’ perspective, it will feel as though we’re not using a system at all – aside from occasionally rolling dice.

Of course, this means I’ll be doing a lot of work behind the scenes – figuring out which skill was rolled, what the difficulty was, what modifiers apply, and so on. That might be exhausting. But I’ve played and run mechanics-heavy systems for years, and I’m confident in my experience. My biggest concern is that players may struggle to connect the dice roll with the outcome. I just hope they don’t feel discouraged if that happens.

Character Creation

Warhammer’s standard character creation process is designed to encourage players to create characters that reflect the setting’s probabilities – in other words, to embrace randomness. However, the system doesn’t strictly enforce this. If a player is willing to give up the equivalent of one or two sessions’ worth of XP, they can essentially hand-pick everything.

I decided to remove the “no XP penalty, choose whatever you like” option for my players. Instead, I offered them more rerolls at various stages. My goal was to nudge them away from always playing the same types of characters, to encourage them to try something different, and to reflect the setting – where playing a “commoner” character is totally normal, at least that’s how I understand it.

I also ensured that players’ characteristics would be above average overall, and they had the option to spend XP to swap stats around or reroll them. As a result, after Session 0, our party consisted of: two priests, one soldier, one sailor, one townsman, and one artist. Almost everyone was satisfied with their career – in fact, only one player rolled for all their career options. The rest chose to accept the bonus XP instead. And that one player wasn’t unhappy with their career – they just saw career rerolling as cheap and were hoping to land something that allowed spellcasting.

Even though none of the players had used the system before, no one found it overly difficult. While I had them roll for everything privately in advance, filling in their sheets, deciding on advancements, and spending XP still took an entire session.

Preparation

I decided to split my game prep into two categories: book-based and session-based. At the start of each new book, I plan to re-read that book from the beginning so I have a solid grasp of what’s expected and where the players are headed.

For each session, I’ll keep separate notes in a dedicated document — especially for encounters and events the players are likely to face. When it comes to descriptions, I plan to use AI tools to help me out, since I know that’s one of my weaker areas. Reviewing others’ experiences and all the alternate paths the book provides will help me decide which options suit my group best — and that’s something I actually find pretty fun.

Using PDF tools, I’ve already extracted images from the books, separated out handouts and NPC portraits. I plan to share the handouts with any characters who are literate, and having NPC images prepared will let me show them to players quickly during the game, as needed.

Companion Books

Each adventure book in the campaign is accompanied by a companion volume. Instead of cramming general setting details, city descriptions, or information about various organizations into the main book, they’ve smartly delegated all of that to the companion books. This has freed up space in the core books, allowing them to stay tightly focused on the story.

The first companion is packed with lore about the setting. Later companions include optional side adventures and other extras. For example, the third book’s companion focuses heavily on political intrigue and introduces a large cast of extra NPCs to the plot– who are optional and only appear in the companion material.

Technically, the main books alone are enough to run the campaign. But when combined with the companions, you suddenly have a vast library of content at your disposal. I genuinely feel like I could run this entire campaign three or four different times and have each playthrough feel quite distinct.

Frankly, I’m very happy with the companion books. Whenever I’ve had questions about the world, most of the answers I needed were right there in those pages.

Conclusion

As the campaign progresses, we’ll see how well these plans and system tweaks hold up – and how much both my players and I enjoy them. I still don’t fully understand why Enemy Within is praised quite this much, aside from being the first long-form published campaign, being set in Warhammer’s grimdark world, and simply offering a lot of content.

That said, I’ve been really impressed by the sheer density of material and the richness of the story. It’s clear that a lot of care and thought went into designing the experience.