coc-mythos-reference

name	coc-mythos-reference
description	Provide spoiler-aware Mythos references for COC mode. Use for monsters, deities, spells, tomes, artifacts, combat stats, source pages, and Keeper-only lookup during scenario preparation or play.

COC Mythos Reference

Use

Use this skill for Keeper-side lookup of Mythos entities, tomes, spells, artifacts, and monster stats.

Spoiler Safety

Do not reveal true monster identities, secret spell effects, hidden tome contents, or scenario answers to the player without [spoiler_warning] and confirmation.

Sources

Prefer structured scenario JSON and source maps first. Use PDFs for detailed lookup only when needed, then summarize rather than quoting long passages.

Monster Presentation Contract

Every entry in references/rules-json/monsters.json carries a structured presentation block (Keeper Rulebook Ch14 p.280-282). Honor it whenever that monster is in play:

• never_name_until — do not speak the creature's true name until pacing horror_stage reaches this stage (default revelation). Climb the Ch10 presentation ladder first.
• sensory_signature — sample early-stage scenes from these sensory strings (smell, sound, residue, wrong geometry). Prefer the director's mythos_presentation.sensory_signature_sample when present.
• death_residue — when a body or remains are found, describe this residue rather than inventing a clean corpse. Deities and Great Old Ones at 0 HP are dispersed or banished, not killed — their residue reflects absence, collapse, or unmaking, never a mundane corpse.
• combat_goal — run the fight toward kill, capture, flee, or ritual. Intelligent species do not fight to the death (p.281).
• retreat_below_hp_fraction — when current HP falls below this fraction of maximum, the creature attempts retreat or disengagement. Mindless threats may leave this null.

Lookup is by structured monster id only (monster_ids / monster_id on the active scene or threat fronts). Never infer a creature's identity by scanning player-facing prose.

Tome Reading

When an investigator studies a Mythos tome (Keeper Rulebook Ch11 p.217-226), drive the mechanical phases through coc_tomes.TomeSession (skim → initial → full → research). Route returned san_loss_expr through SanitySession; merge returned CM gains into the character sheet. Do not invent study weeks, CMI/CMF, or Mythos Rating — read them from tomes.json.

Sensory description (p.224-226). Present the physical book before its contents: binding, smell, weight, ink that seems wrong, pages that resist or invite the eye. Early contact is atmosphere and table-of-contents level (skim); deeper phases unlock structured Mythos insight, not a lore dump.

Book as personality. Treat a major tome as a presence with temperament — jealous, seductive, pedantic, hostile — that colors how knowledge arrives. The book's "voice" is Keeper framing; mechanical outcomes still come from the engine (CM, SAN expression, weeks, research roll contract).

Plot-critical tomes must not dead-end (p.211-212). Language and other failure gates may block ordinary study, but when the scenario requires the tome (plot_critical=True), skip the hard stop and continue with keeper_note: skip_failure_gate. Never strand the investigation on a failed Own Language / Other Language check for a book the plot needs open.