diff --git a/src/GEval/Core.hs b/src/GEval/Core.hs
index 6f6bef2..bbc9c8f 100644
--- a/src/GEval/Core.hs
+++ b/src/GEval/Core.hs
@@ -213,7 +213,10 @@ getExpectedDirectory :: GEvalSpecification -> FilePath
 getExpectedDirectory spec = fromMaybe outDirectory $ gesExpectedDirectory spec
                             where outDirectory = gesOutDirectory spec
 
-data GEvalSpecialCommand = Init | LineByLine | WorstFeatures | Diff FilePath | PrintVersion
+data GEvalSpecialCommand = Init
+                           | LineByLine | WorstFeatures
+                           | Diff FilePath | MostWorseningFeatures FilePath
+                           | PrintVersion
 
 data ResultOrdering = KeepTheOriginalOrder | FirstTheWorst | FirstTheBest
 
diff --git a/src/GEval/LineByLine.hs b/src/GEval/LineByLine.hs
index 2631341..eaa6b85 100644
--- a/src/GEval/LineByLine.hs
+++ b/src/GEval/LineByLine.hs
@@ -12,6 +12,7 @@ module GEval.LineByLine
         runWorstFeatures,
         runLineByLineGeneralized,
         runDiff,
+        runMostWorseningFeatures,
         runDiffGeneralized,
         LineRecord(..),
         ResultOrdering(..)
@@ -212,6 +213,17 @@ runDiff ordering otherOut spec = runDiffGeneralized ordering otherOut spec consu
         formatScoreDiff :: Double -> Text
         formatScoreDiff = Data.Text.pack . printf "%f"
 
+runMostWorseningFeatures :: ResultOrdering -> FilePath -> GEvalSpecification -> IO ()
+runMostWorseningFeatures ordering otherOut spec = runDiffGeneralized ordering' otherOut spec consum
+  where ordering' = forceSomeOrdering ordering
+        consum :: ConduitT (LineRecord, LineRecord) Void (ResourceT IO) ()
+        consum = CC.map prepareFakeLineRecord
+                 .| (worstFeaturesPipeline spec)
+        prepareFakeLineRecord :: (LineRecord, LineRecord) -> LineRecord
+        prepareFakeLineRecord (LineRecord _ _ _ _ scorePrev, LineRecord inp exp out c score) =
+          LineRecord inp exp out c (score - scorePrev)
+
+
 runDiffGeneralized :: ResultOrdering -> FilePath -> GEvalSpecification -> ConduitT (LineRecord, LineRecord) Void (ResourceT IO) a -> IO a
 runDiffGeneralized ordering otherOut spec consum = do
   (inputSource, expectedSource, outSource) <- checkAndGetFilesSingleOut True spec
diff --git a/src/GEval/OptionsParser.hs b/src/GEval/OptionsParser.hs
index d55335f..aeeb58b 100644
--- a/src/GEval/OptionsParser.hs
+++ b/src/GEval/OptionsParser.hs
@@ -55,7 +55,13 @@ optionsParser = GEvalOptions
                     ( long "diff"
                       <> short 'd'
                       <> metavar "OTHER-OUT"
-                      <> help "compare results")))
+                      <> help "compare results"))
+                <|>
+                (MostWorseningFeatures <$> strOption
+                    ( long "most-worsening-features"
+                      <> short 'm'
+                      <> help "Print a ranking of the \"most worsening\" features, i.e. features that worsen the score the most when comparing outputs from two systems.")))
+
    <*> ((flag' FirstTheWorst
          (long "sort"
           <> short 's'
@@ -205,6 +211,9 @@ runGEval''' (Just WorstFeatures) ordering spec = do
 runGEval''' (Just (Diff otherOut)) ordering spec = do
   runDiff ordering otherOut spec
   return Nothing
+runGEval''' (Just (MostWorseningFeatures otherOut)) ordering spec = do
+  runMostWorseningFeatures ordering otherOut spec
+  return Nothing
 
 initChallenge :: GEvalSpecification -> IO ()
 initChallenge spec = case gesExpectedDirectory spec of