diff --git a/src/simulator/crates/mc-player-api/tests/common/mod.rs b/src/simulator/crates/mc-player-api/tests/common/mod.rs
index d267fde1..acad9fde 100644
--- a/src/simulator/crates/mc-player-api/tests/common/mod.rs
+++ b/src/simulator/crates/mc-player-api/tests/common/mod.rs
@@ -24,7 +24,31 @@
 use mc_ai::evaluator::ScoringWeights;
 use mc_ai::tactical::state::{TacticalBuildingSpec, TacticalUnitSpec};
 use mc_state::game_state::{GameState, MapUnit, PlayerState};
-use mc_units::{CombatStats, UnitStats, UnitsCatalog};
+use mc_units::{UnitStats, UnitsCatalog};
+
+/// Unit ids the bench harness sources from the canonical content store.
+///
+/// Single source of truth: both the runtime `UnitsCatalog` (`UnitStats`) and the
+/// tactical `ai_unit_catalog` (`TacticalUnitSpec`) deserialize from the SAME
+/// `public/resources/units/<id>.json` documents the shipped game loads — so the
+/// bench economy (cost, tier, race/tech gates, combat stats, archetype) cannot
+/// drift from the data. The prior inline fixtures were a second, hand-edited
+/// copy that silently diverged (wrong `unit_type`, `build_cost: 0`,
+/// `iron_working` where the JSON says `bronze_working`) and masked real
+/// AI-production bugs. `dwarf_warrior` = tier-1 melee, `dwarf_founder` = settler,
+/// `dwarf_berserker` = the tech-gated tier-2 (iron_working) the legal-actions
+/// round-trip exercises. (The generic `pikeman.json` is a legacy multi-unit
+/// array file; the dwarf-native berserker is the single-object equivalent.)
+const BENCH_UNIT_IDS: &[&str] = &["dwarf_warrior", "dwarf_founder", "dwarf_berserker"];
+
+/// Read a canonical unit document from `public/resources/units/`.
+fn canonical_unit_json(id: &str) -> String {
+    let path = std::path::Path::new(env!("CARGO_MANIFEST_DIR"))
+        .join("../../../../public/resources/units")
+        .join(format!("{id}.json"));
+    std::fs::read_to_string(&path)
+        .unwrap_or_else(|e| panic!("read canonical unit {id} ({}): {e}", path.display()))
+}
 
 /// Mirror of `GdGameState::add_player_militarist` (api-gdext/src/lib.rs).
 ///
@@ -132,50 +156,19 @@ pub fn stamp_personality(state: &mut GameState, pi: usize, clan_id: &str) {
     state.players[pi].promotion_mobility_weight = 1.0;
 }
 
-/// Tactical-AI unit catalog literal. Minimum viable set: the two units
-/// the harness spawns plus one tier-2 melee. Field shape mirrors
-/// `ai_turn_bridge_state.gd::build_unit_catalog`.
+/// Tactical-AI unit catalog (`ai_unit_catalog`) — the buildable specs the MCTS
+/// picker ranks. Deserialized straight from the canonical
+/// `public/resources/units/<id>.json` documents (`TacticalUnitSpec`'s gate
+/// fields are all `#[serde(default)]`), so it stays in lockstep with the data
+/// the shipped game loads via `ai_turn_bridge_state.gd::build_unit_catalog`.
 pub fn build_unit_catalog() -> Vec<TacticalUnitSpec> {
-    vec![
-        TacticalUnitSpec {
-            id: "dwarf_warrior".into(),
-            tier: 1,
-            tech_required: None,
-            // Combat archetype, NOT the "military" ai_tag. The tactical picker
-            // (pick_best_unit_of_type) filters on unit_type ∈ {melee,ranged,siege};
-            // the real units JSON uses "melee" for dwarf_warrior. A bogus
-            // "military" here matches no preferred type, so the picker falls back
-            // to the phantom "warrior" id and the AI never spawns a unit.
-            unit_type: "melee".into(),
-            requires_resource: None,
-            race_required: Some("dwarf".into()),
-            clan_affinity: Vec::new(),
-            archetype: Some("light_melee".into()),
-            requires_building: None,
-        },
-        TacticalUnitSpec {
-            id: "dwarf_founder".into(),
-            tier: 1,
-            tech_required: None,
-            unit_type: "founder".into(),
-            requires_resource: None,
-            race_required: Some("dwarf".into()),
-            clan_affinity: Vec::new(),
-            archetype: None,
-            requires_building: None,
-        },
-        TacticalUnitSpec {
-            id: "pikeman".into(),
-            tier: 2,
-            tech_required: Some("iron_working".into()),
-            unit_type: "melee".into(),
-            requires_resource: None,
-            race_required: None,
-            clan_affinity: Vec::new(),
-            archetype: Some("anti_cavalry".into()),
-            requires_building: None,
-        },
-    ]
+    BENCH_UNIT_IDS
+        .iter()
+        .map(|id| {
+            serde_json::from_str::<TacticalUnitSpec>(&canonical_unit_json(id))
+                .unwrap_or_else(|e| panic!("parse {id} as TacticalUnitSpec: {e}"))
+        })
+        .collect()
 }
 
 /// Tactical-AI building catalog literal. One entry per load-bearing
@@ -211,35 +204,19 @@ pub fn build_building_catalog() -> Vec<TacticalBuildingSpec> {
     ]
 }
 
-/// Runtime `UnitsCatalog` literal — id → `UnitStats`. Mirrors what
-/// `player_api_main.gd::_apply_runtime_units_catalog` harvests from
-/// `public/resources/units/*.json` (the `movement` field maps to
-/// `UnitStats::base_moves`).
+/// Runtime `UnitsCatalog` — id → `UnitStats`. Deserialized from the same
+/// canonical `public/resources/units/<id>.json` documents that
+/// `player_api_main.gd::_apply_runtime_units_catalog` harvests at runtime
+/// (`UnitStats` flattens the JSON's top-level combat line and renames
+/// `movement`→`base_moves`, `cost`→`build_cost`). No hand-maintained stat
+/// literals — the bench picks up real costs/stats and never drifts.
 pub fn build_runtime_units_catalog() -> UnitsCatalog {
     let mut cat = UnitsCatalog::new();
-    cat.insert(UnitStats {
-        id: "dwarf_warrior".into(),
-        base_moves: 2,
-        domain: "land".into(),
-        action_point_capacity: None,
-        capturable: false,
-        ransom_multiplier: 2.0,
-        build_cost: 0,
-        logistics: None,
-        // Mirrors public/resources/units/dwarf_warrior.json combat line.
-        combat: CombatStats { hp: 60, attack: 12, defense: 1, ..Default::default() },
-    });
-    cat.insert(UnitStats {
-        id: "dwarf_founder".into(),
-        base_moves: 2,
-        domain: "land".into(),
-        action_point_capacity: None,
-        capturable: true,
-        ransom_multiplier: 2.0,
-        build_cost: 80,
-        logistics: None,
-        combat: CombatStats::default(),
-    });
+    for id in BENCH_UNIT_IDS {
+        let stats: UnitStats = serde_json::from_str(&canonical_unit_json(id))
+            .unwrap_or_else(|e| panic!("parse {id} as UnitStats: {e}"));
+        cat.insert(stats);
+    }
     cat
 }
 
diff --git a/src/simulator/crates/mc-player-api/tests/legal_actions_round_trip.rs b/src/simulator/crates/mc-player-api/tests/legal_actions_round_trip.rs
index 5947985d..4b48ff0f 100644
--- a/src/simulator/crates/mc-player-api/tests/legal_actions_round_trip.rs
+++ b/src/simulator/crates/mc-player-api/tests/legal_actions_round_trip.rs
@@ -78,10 +78,10 @@ fn per_city_legal_actions_dispatch_without_error() {
         "own city must have legal_actions populated; queue is empty so QueueProduction \
          for catalog members should appear"
     );
-    // 3 unit catalog members + 4 building catalog members → 7 entries when
-    // none require tech (the harness catalogs leave `dwarf_warrior` /
-    // `dwarf_founder` / `granary` / `forge` / `library` / `walls` ungated;
-    // `pikeman` requires `iron_working` which the player hasn't researched).
+    // 3 unit catalog members + 4 building catalog members → 6 buildable entries:
+    // `dwarf_warrior` / `dwarf_founder` / `granary` / `forge` / `library` /
+    // `walls` are ungated; `dwarf_berserker` requires `iron_working` which the
+    // player hasn't researched, so it is filtered out.
     let n_queue = city
         .legal_actions
         .iter()