       @animations.add 'end', [34...53], 12
 
     _initPhysics: ->
+      @physics = @sprite.body
+      @velocity = @physics.velocity
+      @acceleration = @physics.acceleration
+
       @physics.collideWorldBounds = on
 
       @physics.drag.x = 1500


      if @isInMidAir()
        # No force, just air friction.
        @acceleration.x = @runAcceleration / -20 * direction
        return

      else if isStill or landed()

      @jumpMaxDuration = 500
      @jumpVelocityFactor = 1 / 4

      @airFrictionRatio = 1 / 20
      @runAcceleration = 300

      @maxVelocity =
