diff --git a/src/simulator/crates/mc-turn/src/game_state.rs b/src/simulator/crates/mc-turn/src/game_state.rs
index b45cd859..efe977f1 100644
--- a/src/simulator/crates/mc-turn/src/game_state.rs
+++ b/src/simulator/crates/mc-turn/src/game_state.rs
@@ -309,6 +309,13 @@ pub struct GameState {
     /// `CombatOutcome::RansomOffered`.
     #[serde(default)]
     pub ransom_queue: crate::ransom::RansomQueue,
+    /// p2-55f: data-driven combat balance config (ransom durations, XP
+    /// awards, multipliers). Loaded from
+    /// `public/games/age-of-dwarves/data/combat_balance.json` at game start
+    /// via `crate::combat_balance::load_combat_balance`. Defaults to the
+    /// pre-p2-55f hardcoded constants so save migration is no-op.
+    #[serde(default)]
+    pub combat_balance: crate::combat_balance::CombatBalance,
     /// p3-10b: per-lair-tile siege pressure state. Keyed by `(col, row)`
     /// of the lair tile. Bridge layer ticks pressure each turn via
     /// `mc_combat::lair::tick_siege` / `decay_siege`; entries are removed