Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add medy-gribkov/arcana --skill game-enginesgit clone --depth 1 https://github.com/medy-gribkov/arcanaWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/medy-gribkov/arcana/game-engines)<a href="https://agentmods.dev/skills/medy-gribkov/arcana/game-engines"><img src="https://agentmods.dev/badge/skills/medy-gribkov/arcana/game-engines/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/medy-gribkov/arcana/game-engines"><img src="https://agentmods.dev/badge/skills/medy-gribkov/arcana/game-engines.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00028 | $0.03159 |
| Opus 5 | $0.00014 | $0.01580 |
| Sonnet 5 | $0.00006 | $0.00632 |
| Haiku 4.5 | $0.00003 | $0.00316 |
Grade A, and why
game-engines scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 11d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 390 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Game Engines & Frameworks
Engine Comparison
┌─────────────────────────────────────────────────────────────┐
│ ENGINE COMPARISON │
├─────────────────────────────────────────────────────────────┤
│ UNITY (C#): │
│ ├─ Best for: 2D/3D, Mobile, Indie, VR/AR │
│ ├─ Learning: Moderate │
│ ├─ Performance: Good (IL2CPP for native) │
│ └─ Market: 70%+ of mobile games │
│ │
│ UNREAL (C++/Blueprints): │
│ ├─ Best for: AAA, High-end graphics, Large teams │
│ ├─ Learning: Steep (C++) / Easy (Blueprints) │
│ ├─ Performance: Excellent │
│ └─ Market: Major console/PC titles │
│ │
│ GODOT (GDScript/C#): │
│ ├─ Best for: 2D games, Learning, Open source │
│ ├─ Learning: Easy │
│ ├─ Performance: Good for 2D, Improving for 3D │
│ └─ Market: Growing indie scene │
└─────────────────────────────────────────────────────────────┘
Unity Architecture
UNITY COMPONENT SYSTEM:
┌─────────────────────────────────────────────────────────────┐
│ GameObject │
│ ├─ Transform (required) │
│ ├─ Renderer (MeshRenderer, SpriteRenderer) │
│ ├─ Collider (BoxCollider, CapsuleCollider) │
│ ├─ Rigidbody (physics simulation) │
│ └─ Custom MonoBehaviour scripts │
│ │
│ LIFECYCLE: │
│ Awake() → OnEnable() → Start() → FixedUpdate() → │
│ Update() → LateUpdate() → OnDisable() → OnDestroy() │
└─────────────────────────────────────────────────────────────┘
What ships with it
3 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 11d ago First seen · 390 lines · 28 tokens per session scan A aaa95ab22b18
game-engines is a skill published in the GitHub repository medy-gribkov/arcana (1 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 28 tokens to every session and 3,159 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
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