Axiom axiom-games

Use when building ANY 2D or 3D game with SpriteKit, SceneKit, or RealityKit. Covers scene graphs, ECS, physics, actions, game loops, rendering, SwiftUI integration.

install

source · Clone the upstream repo

git clone https://github.com/CharlesWiltgen/Axiom

Claude Code · Install into ~/.claude/skills/

T=$(mktemp -d) && git clone --depth=1 https://github.com/CharlesWiltgen/Axiom "$T" && mkdir -p ~/.claude/skills && cp -r "$T/.claude-plugin/plugins/axiom/skills/axiom-games" ~/.claude/skills/charleswiltgen-axiom-axiom-games && rm -rf "$T"

manifest: .claude-plugin/plugins/axiom/skills/axiom-games/SKILL.md

source content

Games

You MUST use this skill for ANY game development, SpriteKit, SceneKit, RealityKit, or interactive simulation work.

Quick Reference

Symptom / Task	Reference
Building a SpriteKit game	See `skills/spritekit.md`
SpriteKit API lookup	See `skills/spritekit-ref.md`
Physics contacts not firing	See `skills/spritekit-diag.md`
Frame rate drops (SpriteKit)	See `skills/spritekit-diag.md`
Touches not registering	See `skills/spritekit-diag.md`
Memory spikes in gameplay	See `skills/spritekit-diag.md`
Coordinate confusion	See `skills/spritekit-diag.md`
Scene transition crashes	See `skills/spritekit-diag.md`
Objects tunneling through walls	See `skills/spritekit-diag.md`
SpriteKit node/action reference	See `skills/spritekit-ref.md`
SceneKit maintenance/migration	See axiom-graphics (skills/scenekit.md)
SceneKit API / migration mapping	See axiom-graphics (skills/scenekit-ref.md)
RealityKit (3D, ECS, AR)	See axiom-graphics (skills/realitykit.md)
RealityKit API reference	See axiom-graphics (skills/realitykit-ref.md)
RealityKit diagnostics	See axiom-graphics (skills/realitykit-diag.md)

External Routes

These topics are part of the broader games/3D domain but live in separate skill suites:

SceneKit (3D — soft-deprecated iOS 26):

Maintenance and migration planning → See axiom-graphics (skills/scenekit.md)
API reference and migration mapping → See axiom-graphics (skills/scenekit-ref.md)

RealityKit (3D — modern):

ECS architecture, AR, SwiftUI integration → See axiom-graphics (skills/realitykit.md)
API reference → See axiom-graphics (skills/realitykit-ref.md)
Troubleshooting → See axiom-graphics (skills/realitykit-diag.md)

Decision Tree

digraph games {
    start [label="Game development" shape=ellipse];
    what [label="Which framework?" shape=diamond];
    sprite_what [label="SpriteKit need?" shape=diamond];

    start -> what;
    what -> sprite_what [label="SpriteKit (2D)"];
    what -> "axiom-graphics/scenekit" [label="SceneKit (3D legacy)"];
    what -> "axiom-graphics/realitykit" [label="RealityKit (3D modern)"];

    sprite_what -> "skills/spritekit.md" [label="architecture/patterns"];
    sprite_what -> "skills/spritekit-ref.md" [label="API lookup"];
    sprite_what -> "skills/spritekit-diag.md" [label="broken/slow"];
}

Building/designing a 2D SpriteKit game? →
```
skills/spritekit.md
```
How to use a specific SpriteKit API? →
```
skills/spritekit-ref.md
```
SpriteKit broken or performing badly? →
```
skills/spritekit-diag.md
```
Maintaining existing SceneKit code? → See axiom-graphics (skills/scenekit.md)
SceneKit API reference or migration mapping? → See axiom-graphics (skills/scenekit-ref.md)
Building new 3D game or experience? → See axiom-graphics (skills/realitykit.md)
How to use a specific RealityKit API? → See axiom-graphics (skills/realitykit-ref.md)
RealityKit entity not visible, gestures broken, performance? → See axiom-graphics (skills/realitykit-diag.md)
Migrating SceneKit to RealityKit? → See axiom-graphics (skills/scenekit.md) (migration tree) + See axiom-graphics (skills/scenekit-ref.md) (mapping table)
Building AR game? → See axiom-graphics (skills/realitykit.md)
Want automated SpriteKit code scan? →
```
spritekit-auditor
```
agent

Automated Scanning

SpriteKit audit → Launch

spritekit-auditor

agent or

/axiom:audit spritekit

Physics bitmask issues
Draw call waste (SKShapeNode in gameplay)
Node accumulation (missing cleanup)
Action memory leaks (strong self)
Coordinate confusion
Touch handling issues
Missing object pooling
Missing debug overlays

Critical Patterns

SpriteKit (

skills/spritekit.md

PhysicsCategory struct with explicit bitmasks (default
```
0xFFFFFFFF
```
causes phantom collisions)
Camera node pattern for viewport + HUD separation
SKShapeNode pre-render-to-texture conversion
```
[weak self]
```
in all
```
SKAction.run
```
closures
Delta time with spiral-of-death clamping

SpriteKit diagnostics (

skills/spritekit-diag.md

5-step bitmask checklist (2 min vs 30-120 min guessing)
Debug overlays as mandatory first diagnostic step
Tunneling prevention flowchart
Memory growth diagnosis via
```
showsNodeCount
```
trending

Anti-Rationalization

Thought	Reality
"SpriteKit is simple, I don't need a skill"	Physics bitmasks default to 0xFFFFFFFF and cause phantom collisions. The bitmask checklist catches this in 2 min.
"I'll just use SKShapeNode, it's quick"	Each SKShapeNode is a separate draw call. 50 of them = 50 draw calls. spritekit.md has the pre-render-to-texture pattern.
"I can figure out the coordinate system"	SpriteKit uses bottom-left origin (opposite of UIKit). Anchor points add another layer. spritekit-diag.md Symptom 6 resolves in 5 min.
"Physics is straightforward"	Three different bitmask properties, modification rules inside callbacks, and tunneling edge cases. spritekit.md Section 3 covers all gotchas.
"The performance is fine on my device"	Performance varies dramatically across devices. spritekit.md Section 6 has the debug overlay checklist.
"SceneKit is fine for our new project"	SceneKit is soft-deprecated iOS 26. No new features, only security patches. axiom-scenekit has the migration decision tree.
"ECS is overkill for a simple 3D app"	You're already using ECS — Entity + ModelComponent. axiom-realitykit shows how to scale from simple to complex.
"I don't need collision shapes for taps"	RealityKit gestures require CollisionComponent. axiom-realitykit-diag diagnoses this in 2 min vs 30 min guessing.

Example Invocations

User: "I'm building a SpriteKit game" → See

skills/spritekit.md

User: "My physics contacts aren't firing" → See

skills/spritekit-diag.md

User: "How do I create a physics body from a texture?" → See

skills/spritekit-ref.md

User: "Frame rate is dropping in my game" → See

skills/spritekit-diag.md

User: "What action types are available?" → See

skills/spritekit-ref.md

User: "Objects pass through walls" → See

skills/spritekit-diag.md

User: "I need to build a 3D game" → Invoke: See axiom-graphics (skills/realitykit.md)

User: "I'm migrating from SceneKit to RealityKit" → Invoke: See axiom-graphics (skills/scenekit.md) + See axiom-graphics (skills/scenekit-ref.md)

User: "Can you scan my SpriteKit code for common issues?" → Launch

spritekit-auditor

agent