Art bibles and style guides

An art bible (often called a style guide) is the document that tells every artist on a project what the game should look like and why. Ricky Baba, writing as an art director, says it should aim for "consistency and clarity" in style, shape, size, line, colour, perspective and anatomy (Game Developer: Art Direction in Video Games - A roadmap for…).

Most studio art bibles are internal and never published. This page collects what the public examples and practitioner articles say they contain.

#Contents of an art bible

Section	What it answers	Published example
Goals and pillars	Why the game looks the way it does	Valve gives three reasons for Team Fortress 2's style: gameplay, readability and branding (GDC 2008)
Influences and reference	Which art traditions to borrow from	TF2 adopted the conventions of commercial illustrator J.C. Leyendecker and showed work by Dean Cornwell and Norman Rockwell (GDC 2008). See gathering and using reference
Readability rules	What the player must be able to read at a glance	TF2: "Distinctive silhouettes", "Highest contrast at chest level, where weapon is held" (GDC 2008). See silhouette, visual hierarchy and readability
Value and colour	Palettes, value structure, lighting colour	TF2: "Shading obeys a warm-to-cool hue shift. Shadows go to cool, not black" (GDC 2008). Valve's Dota 2 guide covers "value patterning and a coherent colour palette" (CG Channel). See value, colour for environments
Shape and material language	How factions, regions or eras differ	TF2's Red team: "Warm colors", "Natural materials", "Angular geometry"; Blue: "Cool colors", "Industrial materials", "Orthogonal forms" (GDC 2008). See shape language
Detail and rest	Where detail goes and where the eye rests	The Dota 2 guide "explores ideas of rest and detail and of evaluating assets in context" (CG Channel)
Technical rules	Scale, texel density, trim layouts, budgets	Naughty Dog's trim pipeline mapped panels at 512 px per metre and shipped Substance Designer templates, test assets and tutorials for the team (ArtStation)

The technical section often lives beside the art bible in a wiki: naming conventions, metrics, polygon and triangle budgets and export rules. The Level Design Book's metrics page is a good model for that kind of reference (The Level Design Book: Metrics).

#Published examples

ExampleTeam Fortress 2 (Valve, GDC 2008)

Jason Mitchell's GDC 2008 deck "Stylization with a Purpose" is a rare public example of a major studio explaining its visual rules (GDC 2008: Stylization with a Purpose: The Illustrative…). It states rules an artist can check work against:

A value "Gradient from dark feet to light chest", with the highest contrast at chest level where the weapon is (GDC 2008: Stylization with a Purpose: The Illustrative…).
Silhouettes "emphasized with rim highlights rather than dark outlines" (GDC 2008: Stylization with a Purpose: The Illustrative…).
Clothing folds "chosen to echo silhouette shapes" (GDC 2008: Stylization with a Purpose: The Illustrative…).
Environments with an "Impressionistic painterly look" and "Team distinction through material hue/value/saturation" (GDC 2008: Stylization with a Purpose: The Illustrative…).

Each rule is short, specific and tied to a gameplay reason, which makes the rules easy to apply.

#When it is written and who uses it

Baba recommends you "create a style guide before other artists join the project" (Game Developer: Art Direction in Video Games - A roadmap for…). If the direction is still forming, he suggests setting aside a daily hour for a week to "reflect, curate, itemize and resolve your work", which gives you the start of a guide (Game Developer: Art Direction in Video Games - A roadmap for…).

Then share it: "Distribute the style guide and have an open forum to discuss the visual direction" (Game Developer: Art Direction in Video Games - A roadmap for…). A good guide gives artists "a visual and mental starting point rather than having them start with an intimidating blank canvas" (Game Developer: Art Direction in Video Games - A roadmap for…).

For environment teams, planning documents feed the guide. EMC3D's trim-sheet planning video walks through a colour overlay plan and using the blockout to plan trims before production (YouTube: What Does Good Trim Sheet Planning &…).

#Common mistakes

A mood board instead of a guide. Pretty reference without rules leaves every artist to interpret it differently.
No reasons. Rules without the "why" get broken as soon as a case is not covered.
Written once, never updated. Kits and trims change in production (ArtStation: Indiana Jones and the Great Circle: Tomb Kit); the guide should follow.
Separate from the technical rules. Texel density, naming and budgets belong in the same place artists look.

#Further reading and watching

Stylization with a Purpose: The Illustrative World of Team Fortress 2 (Valve, GDC 2008)

the clearest published example of a game's visual rules and the reasons behind them. Intermediate, free.

PaperIntermediateFree

Valve releases useful character design guide (CG Channel)

summary and link to Valve's Dota 2 character art guide. Beginner, free.

WebBeginnerFree

Art Direction in Video Games (Ricky Baba, Game Developer)

an art director on writing and sharing a style guide. Beginner, free.

ArticleBeginnerFree

The Last of Us Part I: Trim Pipeline (Matthew Trevelyan Johns)

technical rules (512 px/m, shared trim layouts) documented for a whole team. Intermediate, free.

BreakdownIntermediateFree

What Does Good Trim Sheet Planning & Preparation Look Like? (EMC3D)

planning trims from the blockout with colour overlays. Intermediate, free.

VideoIntermediateFree

References

Ricky Baba · Art Direction in Video Games - A roadmap for finishing your projects · Game Developer, 2014 · article · accessed 2026-10-21

Jason Mitchell (Valve) · Stylization with a Purpose: The Illustrative World of Team Fortress 2 · GDC 2008 (slides, Valve), 2008 · talk · accessed 2026-10-21

Jim Thacker · Valve releases useful character design guide · CG Channel, 2012 · article · accessed 2026-10-21

Matthew Trevelyan Johns · The Last of Us: Part I...Trim Pipeline · ArtStation, 2023 · article · accessed 2026-10-21

The Level Design Book · Metrics · The Level Design Book · web · accessed 2026-10-21

Paweł Kostecki · Indiana Jones and the Great Circle: Tomb Kit · ArtStation, 2025 · article · accessed 2026-10-21

Vytautas Katarzis · Indiana Jones and The Great Circle: Shanghai Environment Breakdowns · ArtStation, 2025 · article · accessed 2026-10-21

EMC3D - Game Art · What Does Good Trim Sheet Planning & Preparation Look Like? (Part 2) · YouTube, 2024 · video · accessed 2026-10-21