Canon Rules

Athenaeum methodological note. Correspondent of record: Vel Asharen.

How This World Remembers

The first playthrough of any campaign sets that campaign's outcome in stone. Once a story is played to completion, the events of that campaign become canon for every campaign that follows in this world.

The Athenaeum's working model of Yggy is that the world remembers what happens in it. A duchy that fell in one party's hands stays fallen. A noble line that ended in another's stays ended. A treaty signed in blood stays signed. The correspondent's records update accordingly.

This is not a metaphysical claim about the world's nature. It is a methodological claim about the records: the Athenaeum does not undo entries.

Inheritance

Future campaigns inherit the world the previous parties left behind. New characters walk into kingdoms whose recent history was written by characters who came before them — sometimes as legend, sometimes as scar. The Yggdrasil collection is therefore not a static reference but a living, accumulating timeline.

The introduction text and broad cultural facts in this volume describe the world's baseline state. The Historical Events section is where canon evolves. Any campaign played to completion may add to it.

Practical Notes for the DM

The following sections are DM-facing and not part of the Athenaeum's public collection.

  • The DM keeps the master canon. Anything contradicted in earlier completed campaigns overrides later work.
  • When a campaign concludes, its Outcome entry should be promoted into Historical Events.
  • Players are encouraged to ask, before making a campaign-altering decision: do you want this to be true forever?

Extra Rules

  • When entering saving throws due to necrotic damage, the body part struck is inoperable until cured by a 2nd-level healing spell or a spell of purging effects. If players fail to cure the affected body part before a long rest, the body part must be replaced with a prosthetic.
  • Death due to necrotic damage prevents revival via the revivify spell. Players can still be revived with wish, or with necromancy spells that turn them into undead.