From Dungeon Keeper to Dwarf Fortress: The Impossible Challenge of Building Colony Sims

The Blueprint That Outran Its Creators, Dungeon Keeper's Legacy

When Bullfrog released Dungeon Keeper in 1997, it didn't just let players be evil, it let them be the evil mastermind who never lifts a finger directly. The game set a radical template: indirect control of autonomous minions in a persistent, simulated space. Instead of clicking units to issue every command, you were a manager, nudging goblins and demons toward resource gathering, combat, and even recreation. The minions had individual AI, they trained, fought, sometimes idled, and their behavior generated a sense of emergent life that no scripted campaign could match.

This approach was decades ahead of its time, but the technology of the 1990s limited how far Bullfrog could push. The "evil" charm masked a deep simulation challenge: how do you grant individual agency to dozens of creatures while keeping the player engaged as an overseer? Bullfrog's solution, giving minions their own goals and letting the player reward or punish, created emergent comedy (a Bile Demon failing to kill a chicken, a Vampire complaining about the accommodations) from AI interacting with the environment. Yet the simulation depth was shallow by today's standards; pathfinding often broke, and minion AI could be tricked by simple terrain. Despite these limitations, Dungeon Keeper laid the groundwork for all colony sims to follow. Its core feedback loop, build a space, attract autonomous inhabitants, watch them interact, remains the genre's DNA.

The Simulation-First Philosophy, Dwarf Fortress's Two-Decade Experiment

If Dungeon Keeper planted the seed, Dwarf Fortress grew an entire biome. Created by Tarn and Zach Adams of Bay 12 Games, Dwarf Fortress first appeared publicly in August 2006 and has been in continuous development ever since. Its design philosophy is often described as "simulation first, product second", the world generator treats complexity as its reason for being, not a feature to trim for mass appeal.

The result is unmatched depth. Dwarf Fortress simulates history, geology, weather, animal behavior (including full cat psychology), and the actions of hundreds of dwarves with individual memories, moods, and skills. Every world is unique, generated from tectonic plates upward. Yet this depth came at a cost: ASCII graphics, a steep learning curve, and, for years, no tutorial. In 2017, a survey of the genre's development challenges noted that Dwarf Fortress was considered "halfway to completion" after more than a decade of work. That remark highlighted the genre's core problem: a colony sim can never be truly finished because emergent depth demands infinite iteration on systems.

Despite, or because of, its obscurity, Dwarf Fortress influenced later hits like Minecraft and RimWorld. The former borrowed its blocky terrain and underground digging; the latter took its storytelling engine and streamlined it. Dwarf Fortress's own journey toward accessibility began with its 2022 Steam and itch.io release, published by Kitfox Games. That version added tilesets, music, and an easier start while preserving the underlying simulation. It proved that even the most uncompromising sim must eventually face the usability question, and that players are hungry for depth if you can lower the barrier.

Balancing Depth and Accessibility, The RimWorld Model

RimWorld (2018), designed by Tynan Sylvester and published by Ludeon Studios, succeeded where many had tried: it made the colony sim approachable without losing the emergent magic. The key was subtraction, deciding which simulation layers to keep and which to simplify.

RimWorld kept the individual pawn system from Dwarf Fortress, tracking moods, relationships, and random events that created personal stories. It also implemented a powerful modding framework that lets players add complexity at will. But it dropped whole subsystems: no z-levels (everything happens on a single plane), no fluid or gas physics, no detailed geology. Instead, it focused on narrative AI, a system called the "Storyteller" that dials challenge up and down based on player performance. This is the colony sim's eternal headache: every developer must choose between simulating enough for emergent surprise and not overwhelming players or system performance. RimWorld's success, both critically and commercially, proved that there is a sweet spot. The game became a platform for countless mods that let players add back the complexity they wanted, from realistic body part damage to interstellar trade routes. It proved that the colony sim's strength lies in its modularity: players should be able to tune depth to their taste.

Modern Hybrids and the Complexity Escalation

As the genre matured, developers began escalating simulation complexity into new domains. Klei Entertainment's Oxygen Not Included (2019) replaced medieval dwarves with duplicants in a space colony, but its real innovation was the simulation itself. The game demands "airtight planning" across piping, ventilation, power grids, gases, heat, and liquids. A single overlooked vent can flood your base; a poorly insulated heat source can melt everything. The result is emergent behavior that feels organic, but also potential dead ends if players misdesign their systems.

More recent titles have tackled the emergence-versus-control problem from new angles. Against the Storm (2023) blends colony sim with roguelike mechanics: each settlement is a temporary run, forcing players to optimize quickly while managing the mood of beaver, lizard, and harpy workers. The procedural weather, orders, and glade events create emergent stories within short, focused sessions, a deliberate contrast to Dwarf Fortress's endless sprawl. Meanwhile, Songs of Syx (2023) scales up to city-sized colonies with thousands of citizens, simulating a full economy and political system. It proves that even the most ambitious simulation can find an audience if it provides clear feedback loops and a gradual learning curve. Each new hybrid introduces fresh balancing headaches, but they also demonstrate that the genre is far from reaching a ceiling.

The Unsolved Problem, Emergence vs. Narrative Control

Perhaps the greatest challenge of colony sim development is the unsolved tension between emergence and narrative control. These games build systems that generate stories, not scripted plots. That is fundamentally different from traditional game design, and harder to test, debug, and polish. A scripted RPG can be playtested for pacing; a colony sim must be playtested for systemic weirdness.

Too much emergence can produce nonsense or frustrating outcomes, the infamous Dwarf Fortress bug where a cat falling down a well triggered a cascade of dwarf deaths is a legend for a reason. Too little emergence makes the game feel mechanical and predictable. The perfect balance is elusive even for veteran developers. In 2017, a feature exploring the genre's history called this the central tension of colony sim design, and it remains unresolved nearly a decade later. Evidence of this struggle appears in modern entries like Going Medieval and Stranded: Alien Dawn, which add more polished storytelling and preset scenarios but still rely on emergent AI to generate replayability.

Why They Keep Digging

If building a colony sim is so hard, an endless loop of system tinkering, performance optimization, and unpredictable player behavior, why do developers keep doing it? The answer lies in the unique payoff: player-driven stories that no scripted game can replicate. When a RimWorld colonist befriends a survivor of a pirate raid and then turns traitor during a toxic fallout event, that story belongs to that player. No writer could plan it; no linear narrative could capture its chaos.

The Dwarf Fortress Steam release in 2022 marked a watershed moment: it showed that accessibility and depth are not mutually exclusive. Tools like the Unity engine and modding frameworks have lowered the barrier to entry for new developers, and hybrids are introducing colony sim mechanics to broader audiences. As large language models creep into game story tools, the boundary between scripted and emergent may blur even further, but the core struggle of building a world that runs itself will remain as brutal as ever. The god machine will never be perfect, but that imperfection is precisely what makes it worth building.