diff --git a/douzero/server/battle.py b/douzero/server/battle.py
index fad1e5a..a583324 100644
--- a/douzero/server/battle.py
+++ b/douzero/server/battle.py
@@ -43,16 +43,16 @@ def battle_logic(baseline : Baseline, battle : Battle):
 
     challenge_success = False
     if battle.challenger_position == 'landlord':
-        if landlord_wp - 0.15 > baseline.landlord_wp:
+        if landlord_wp / baseline.landlord_wp > 1.2:
             landlord_wp, farmer_wp, landlord_adp, farmer_adp = \
                 _second_eval(landlord_wp, farmer_wp, landlord_adp, farmer_adp)
-            if landlord_wp - 0.15 > baseline.landlord_wp:
+            if landlord_wp / baseline.landlord_wp > 1.2:
                 challenge_success = True
     else:
-        if farmer_wp - 0.15 > baseline.farmer_wp:
+        if farmer_wp / baseline.farmer_wp > 1.2:
             landlord_wp, farmer_wp, landlord_adp, farmer_adp = \
                 _second_eval(landlord_wp, farmer_wp, landlord_adp, farmer_adp)
-            if farmer_wp - 0.15 > baseline.farmer_wp:
+            if farmer_wp / baseline.farmer_wp > 1.2:
                 challenge_success = True
     if challenge_success:
         challenger_baseline['rank'] = baseline.rank + 1