Simplify creature update

src/Dodge/Item/Weapon/BatteryGuns.hs

@@ -404,7 +404,7 @@ shootTeslaArc' :: ItemParams -> Point2 -> Float -> World -> (World,ItemParams)
 shootTeslaArc' ip pos dir w = 
     (w & randGen .~ g
        & instantParticles .:~ aTeslaArcAt col newarc
-    , ip & currentArc .~ Just newarc
+    , ip & currentArc ?~ newarc
     )
   where
     (col,g) = takeOne [white,azure,blue,cyan] & runState $ _randGen w
@@ -487,6 +487,7 @@ shootLaser it cr = instantParticles .:~ lasRayAt (_lasColor $ _itParams it) dam
     phasev = _phaseV . _itParams $ _crInv cr IM.! _crInvSel cr
     dam = _lasDamage $ _itParams it
 
+
 shootDualLaser :: Item -> Creature -> World -> World
 shootDualLaser it cr w = w'
     & newBeams . positronBeams .:~ dualRayAt (_lasBeam $ _itParams it) itid w (_lasColor $ _itParams it) dam phasev posl dirl