Mechanic Picker (choose 2-3 mechanics that need each other, one page, bot playtest)
/mechanic-picker
A GameSkill original for the step before building: pick two or three game mechanics that work together from 24 cards, scored against your input, day budget and wanted feel, write them on one checked page with a playtest question each, and prove the pair makes a game with a quick bot playtest. Worked example: Lantern Ferry, whose first numbers the bots caught as a one-strategy game.
- License
- MIT
- By
- By GameSkill
Tested by GameSkill
31/31 checks passed on Node (picker, lint, bot playtest) + Chrome headless (grey box) (2026-11-03): trigger, a runnable example, a screenshot and self-check, one job per skill, and English + Chinese docs. Trigger checks match prompts against skill descriptions; they are not a live agent run.
Test reportGameSkill's tested copy
Written and tested by GameSkill for gameskill.dev. The ZIP holds the whole skill: SKILL.md and its Chinese version, scripts, a runnable example, tests, the self-check list and our test report.
A GameSkill original, released under MIT. The ZIP keeps LICENSE and CREDITS.md, which lists the workflow inspiration, the CC0 test assets and the third-party libraries with their licenses.
Self-check
- 最多 3 个机制，最好 2 个互相需要的 / At most 3 mechanics, ideally 2 that need each other
- 先写 brief JSON，再运行挑选器，把前三名给用户选 / Write the brief JSON, run the picker, let the user choose from the top three
- 一页 brief 必须通过 check-brief / The one-page brief must pass check-brief
- 先灰盒，再每次只做一个机制 / Grey box first, then one mechanic at a time
- 总是同一种打法最好就先调数值 / If one strategy always wins, tune before art
- 不把现成游戏当目标 / Never name an existing game as the target
Install
Tell your AI
Install the skill from https://gameskill.dev/skills/mechanic-picker/install.md
GameSkill's tested copy
mkdir -p .claude/skills
curl -fsSL https://gameskill.dev/dl/skills/mechanic-picker.zip -o /tmp/gameskill-mechanic-picker.zip
unzip -oq /tmp/gameskill-mechanic-picker.zip -d .claude/skills
rm /tmp/gameskill-mechanic-picker.zipWhat you get
- 24 mechanic cards in English and Chinese: verb, loop, input, days, what each gives and needs, clashes, one playtest question
- tools/pick.mjs: scores every 2- or 3-card combination against the brief and writes a one-page build brief
- tools/check-brief.mjs: PASS only for 2-3 mechanics, a build order, a question per mechanic, one page, no remake of another game
- Lantern Ferry: brief, grey box and a bot playtest (random player, fixed loads, best-plan search)
Good fit
- A game idea with no mechanics yet
- Scoping a jam or weekend game
- A project that keeps growing features without getting more fun
Not for
- Building the mechanics: pair it with godot-one-mechanic or an engine skill
- Balancing a big game: the bot playtest fits small rule sets
Try this prompt
I want a small keyboard game about a ferry carrying lanterns before the tide, two days to build. Pick two mechanics that need each other, write the one-page brief and lint it.About this skill
Mechanic Picker is a GameSkill original for the step before building. The agent writes the brief as a small JSON file with the user (input device, build days, session length, the feel they want, an optional mechanic they already chose), runs the picker over 24 mechanic cards, shows the top combination and two alternatives, and writes a one-page brief that a lint checks: two or three mechanics, a grey-box step and one build step per mechanic, and a playtest question for each.
When the rules are small, the example shows how to check that the pair really makes a game: a random player, fixed strategies and a best-plan search. In Lantern Ferry, a made-up ferry game, the bots caught the first numbers (carrying the full load was always right), and the tuned levels have a different best load on each level. The idea of picking mechanics from a catalogue before handing them to an agent comes from Gameplay Atlas and Game Dev Cheat Sheet, linked only; the cards, scoring and example are ours.
Related
- godot-one-mechanic to build the picked mechanics one at a time.
- game-design-gdd for the full design document afterwards.
Requirements
- Node 18+ (tools use built-ins only)
- For the example tests only: npm ci (puppeteer-core) and Chrome or Chromium
Topics
FAQ
Based on Gameplay Atlas (idea only) by Gameplay Atlas (no licence, idea only, no cards, text or images used). Ideas only: GameSkill wrote the code and text; CREDITS.md in the ZIP lists every source. · Based on Game Dev Cheat Sheet (idea only) by Game Dev Cheat Sheet (no licence, idea only, no text or prompts used). Ideas only: GameSkill wrote the code and text; CREDITS.md in the ZIP lists every source.
Works well with
Skills the author points to as related or as the better fit for neighbouring tasks.
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Game Design: GDD & Systems
Design systems and mechanics: GDD authorship, gameplay loops, economy balancing and player psychology.
Quick Design (Claude Code Game Studios)
Lightweight spec for small changes — tuning adjustments, minor mechanics.
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