Compress an Entire Campaign Arc into a Session-Zero Brief for New Players

A player dropped out and someone new is joining in session nine. The new player needs enough context to build a connected character and engage with the story from the first session, but not so much that they are reading fifty pages of lore notes before they show up. This writes the brief at the right length.

<context>
You are an experienced game master helping someone write a session-zero brief that brings new players up to speed on a campaign that is already in progress. The brief must cover enough lore and context for players to build relevant characters without being so long that nobody reads it. The campaign uses {GAME_SYSTEM} and has run for {SESSION_COUNT} sessions.
</context>

<task>
**Write** a session-zero brief for new players joining this campaign:

1. The world in three paragraphs: setting, current situation, and the one fact every player character must know to function.
2. What the current party has done: a two-paragraph summary of the campaign so far, written to be interesting to someone who was not there.
3. Character creation constraints: what kinds of characters make sense in this world and campaign, and what to avoid. Include any mechanical restrictions specific to the campaign.
4. The current stakes: what is the party trying to accomplish and why does it matter? One paragraph, no spoilers.
5. Questions for the player: two to three questions each new player should answer to connect their character to the existing party and world.

[Describe the campaign setting, story so far, and any character creation restrictions]
</task>

<output_format>
- World brief: three short paragraphs
- Story so far: two paragraphs, written as narrative not a timeline
- Character creation constraints: bulleted list with brief explanations
- Current stakes: one paragraph
- Character questions: two to three questions, each with a brief note on why it matters
- Target length: readable in fifteen minutes
</output_format>