Regeneration

Sometimes a player-initiated pin contradicts the Shadow Horizon — not the Western Horizon, but the Shadow Horizon. The innkeeper the engine generated as a Strangers faction loyalist with no family ties turns out to be a player’s uncle.

The Shadow Horizon regenerates. Not from scratch. The pinned node (uncle innkeeper) is now a hard constraint — it crosses from the Shadow Horizon into the Western Horizon the moment it’s declared. Every other observed node is also fixed. The engine re-collapses only the unobserved tiles, propagating from the updated constraint set.

Three Regeneration Modes

Absorb — The new pin fits within the existing Shadow Horizon with no conflicts. Pin and done. This is the fast path and should be the common case.

Local — The new pin conflicts with a small cluster of unobserved tiles. Regenerate that neighborhood. Medium cost, localized impact.

Global — The new pin contradicts something structural: faction power balance, quest logic, settlement identity. Regenerate the entire Shadow Horizon for affected layers. Expensive, rare, necessary.

Settlements Solidify Over Time

Regeneration gets cheaper as a settlement is played in more. More tiles are pinned by observation, fewer are available to change. A metropolis visited by ten different parties might have 70% pinned nodes — most regeneration requests will be Absorbs.

The world hardens into canon naturally through play, not GM fiat. See The Shadow Horizon for the full picture of how observed vs. provisional canon works.