Cleanup, trying to diagnose space leak in crit update

src/Dodge/Creature/Impulse.hs

@@ -1,7 +1,7 @@
 module Dodge.Creature.Impulse
     ( impulsiveAIR
-    )
-    where
+    , impulsiveAI
+    ) where
 import Dodge.Data
 import Dodge.Creature.Vocalization
 import Dodge.Creature.Impulse.Movement
@@ -13,15 +13,20 @@ import qualified Data.IntMap.Strict as IM
 import System.Random
 import Control.Lens
 import Control.Monad.Reader
-import Data.Monoid
 import Data.Bifunctor
 
 impulsiveAIR
     :: (Creature -> Reader World Creature)
     -> Creature
     -> World
-    -> (Endo World , Maybe Creature)
-impulsiveAIR impf cr w = bimap Endo Just $ followImpulses w . ($ w) . runReader $ impf cr
+    -> (World -> World , Maybe Creature)
+impulsiveAIR impf cr w = bimap id Just $ followImpulses w . ($ w) . runReader $ impf cr
+
+impulsiveAI :: (World -> Creature -> Creature)
+    -> Creature
+    -> World
+    -> (World -> World , Maybe Creature)
+impulsiveAI impf cr w = bimap id Just $ followImpulses w $ impf w cr
 
 followImpulses 
     :: World