diff --git a/hwe/scenario/scenario_915.json b/hwe/scenario/scenario_915.json
index 521f49d8..184b9743 100644
--- a/hwe/scenario/scenario_915.json
+++ b/hwe/scenario/scenario_915.json
@@ -11,7 +11,8 @@
     ],
     "const": {
         "npcBanMessageProb":0.005,
-        "defaultMaxGeneral": 800
+        "defaultMaxGeneral": 800,
+        "uniqueTrialCoef": 2
     },
     "events": [
         [