Chapter 10 Further Reading

Books

Greg Costikyan, Uncertainty in Games (MIT Press, 2013)
The definitive academic treatment of randomness and uncertainty in game design. Costikyan identifies eleven sources of uncertainty in games (randomness is only one of them) and analyzes how each creates engagement. The book's taxonomy --- which includes performative uncertainty (player skill), analytic complexity (too many options to calculate), hidden information, and narrative anticipation alongside stochastic randomness --- is essential for designers who want to understand why uncertainty works, not just how to implement it. Chapters 4-6 on the relationship between uncertainty and decision-making are directly relevant to the input/output randomness distinction covered in this chapter.

Nassim Nicholas Taleb, Fooled by Randomness (Random House, 2004)
Not a game design book, but an invaluable exploration of how humans systematically misunderstand probability. Taleb, a former options trader, examines survivorship bias, the narrative fallacy (our compulsion to construct causal stories from random events), and the problem of silent evidence (we see the winners, not the losers). Every cognitive bias Taleb describes is active in how players perceive game randomness. Reading this will permanently change how you think about the gap between mathematical fairness and perceived fairness --- the core problem of Chapter 10.

Talks

Keith Burgun, "The Role of Randomness in Game Design" (GDC 2014)
The talk that popularized the input/output randomness distinction in the design community. Burgun argues that input randomness is almost always superior because it creates situations for skill to operate on, while output randomness undermines player agency. His framework is deliberately provocative --- he argues that output randomness should be minimized or eliminated in strategy games --- but even designers who disagree with his conclusions use his terminology. Essential viewing for understanding the theoretical foundation of this chapter's central distinction.

Jake Solomon, "Lessons from XCOM: Balancing Randomness and Strategy" (GDC 2013)
The lead designer of XCOM: Enemy Unknown discusses the specific challenges of building a tactical game around percentage-based hit chances. Solomon is remarkably candid about the game's hidden bonuses, the player perception problems they were designed to solve, and the philosophical tension between mathematical honesty and experiential fairness. His discussion of why they decided to cheat in the player's favor --- and why they were transparent about it post-launch --- is a masterclass in randomness design pragmatism.

Mark Brown, "The Two Types of Random" (Game Maker's Toolkit, 2020)
Brown's accessible, example-driven breakdown of input and output randomness uses Slay the Spire, Spelunky, XCOM, Into the Breach, and Dicey Dungeons to illustrate the concepts. The video is an excellent complement to this chapter's written treatment, with visual demonstrations of how each game sequences randomness and player decisions. Particularly strong on the Into the Breach comparison --- a game that eliminated randomness entirely and still produces deep tactical gameplay.

Papers and Articles

Darius Kazemi, "Loot Drop Best Practices" (GDC 2012 / Tiny Subversions blog)
A practical, implementation-focused talk (with accompanying blog posts) on designing loot tables for games. Kazemi covers weighted probability, diminishing returns, the "birthday paradox" problem (how quickly players notice duplicate drops), and the emotional design of drop rates. His discussion of "feel-good math" --- where the mathematical system is deliberately designed to produce emotionally satisfying results rather than mathematically pure ones --- directly connects to the pseudo-random distribution and pity timer techniques covered in Section 10.6.

Ian Dallas and the Giant Sparrow Team, "Randomness in What Remains of Edith Finch" (GDC 2018 Vault)
A less-discussed but valuable talk about randomness in narrative games. Dallas discusses how controlled randomness in environmental details (which objects are slightly displaced, which lights flicker, which sounds play in the background) creates a sense of lived-in authenticity without the player ever consciously noticing the variation. This is randomness as atmosphere rather than mechanics --- a valuable perspective for designers who think randomness belongs only in combat and loot systems.

"Pseudo-Random Distribution" (Dota 2 Wiki / Liquipedia)
The technical documentation of DOTA 2's PRD implementation, including the C-value tables, the binary search algorithm for computing C from a nominal probability, and empirical measurements of actual proc rates versus stated rates. This is the primary source for Section 10.6's PRD implementation and is worth reading for designers who want to understand the mathematical underpinnings in full detail.

Games to Play

Slay the Spire (2019)
After reading Case Study 2, play Slay the Spire with specific attention to how the game sequences randomness and decisions. Notice that you always know what you can do before you commit. Notice how deckbuilding is probability management. Play at least two complete runs (win or lose) and reflect on whether your losses felt like your fault or the game's fault. If you answer "my fault," you have experienced input randomness design at its best.

Spelunky 2 (2020)
Derek Yu's sequel refines the procedural generation approach of the original. Every death is a lesson because every level is traversable and every hazard is visible before it threatens you. The randomness is the layout; the skill is the navigation. Play five runs and note: do you ever feel the randomness was "unfair"? If not, you are experiencing the gold standard of constrained procedural generation.

Balatro (2024)
A poker-themed roguelike deckbuilder that applies input-randomness principles to an entirely different mechanical foundation than Slay the Spire. You are dealt poker hands (input randomness), and your decisions about which cards to hold, which jokers to buy, and which hands to play are fully informed. An excellent study in how the "present the situation, let the player decide" framework transfers across game genres.

Into the Breach (2018)
The anti-randomness game. Subset Games (the studio behind FTL) designed a tactical game with zero output randomness. Enemy attacks are telegraphed. Damage is exact. Effects are deterministic. The result is a game of pure, crystalline strategy where every failure is demonstrably the player's fault. Play this alongside XCOM and ask yourself: which game produces better stories? Which is more frustrating? The comparison will teach you more about the role of randomness than any textbook chapter.

Hades (2020)
Supergiant Games' roguelike uses randomness at multiple scales: room rewards, boon (ability) selection, enemy encounter composition, and boss variation. Notice how the game presents boon choices as three visible options (input randomness) and how the "mirror of night" permanent upgrades and prophecy system provide deterministic progression alongside randomized runs. Hades demonstrates how to layer randomness with guaranteed progression so that even a "bad luck" run contributes to long-term advancement.