diff --git a/src/game/engine/tests/integration/test_p2_58b_ambient_encounter.gd b/src/game/engine/tests/integration/test_p2_58b_ambient_encounter.gd
index 68672945..5f31b565 100644
--- a/src/game/engine/tests/integration/test_p2_58b_ambient_encounter.gd
+++ b/src/game/engine/tests/integration/test_p2_58b_ambient_encounter.gd
@@ -78,6 +78,11 @@ func _make_state(grid: RefCounted) -> RefCounted:
 	assert_not_null(state, "GdGameState must be registered")
 	## Attach the pre-seeded fauna grid.
 	state.call("set_grid_from_gridstate", grid)
+	## p2-71c — add_player_militarist refuses to spawn without the runtime units
+	## catalog (MapUnit base_moves=0 otherwise). Load it before spawning.
+	var units_json: String = AiTurnBridge._harvest_runtime_units_json()
+	if not units_json.is_empty():
+		state.call("set_units_runtime_catalog_json", units_json)
 	## Add one militarist player. Unit spawns near FAUNA_COL/ROW via
 	## add_player_militarist which places units close to the city.
 	## We use the fauna tile coordinates directly as the city so the unit
@@ -130,6 +135,9 @@ func test_ambient_encounter_count_zero_on_barren_tile() -> void:
 	if not is_instance_valid(state):
 		return
 	state.call("set_grid_from_gridstate", grid)
+	var units_json: String = AiTurnBridge._harvest_runtime_units_json()
+	if not units_json.is_empty():
+		state.call("set_units_runtime_catalog_json", units_json)
 	state.call("add_player_militarist", FAUNA_COL, FAUNA_ROW)
 	state.set("seed", 42)