     @engine = engine
     @entities = engine.e 'blob', 'pos'
   update: (delta) ->
+    for group in groups
+      group -= delta
+      if group < 0
+        group = null
     # Create QuadTree, TODO should not use hard-coding
     quad = new QuadTree -1000, -1000, 1000*2, 1000*2,
       maxchildren: 4

      if entBlob.invincible
        entBlob.invincible -= delta
        entBlob.invincible = null if entBlob.invincible < 0
      if groups[entBlob.group]
        groups[entBlob.group] -= delta
        if groups[entBlob.group] < 0
          groups[entBlob.group] = null
      entObj =
        x: entPos.x - entPos.radius
        y: entPos.y - entPos.radius

  [otherPos, otherBlob] = [other.c('pos'), other.c('blob')]
  # Run away from the other
  direction = Math.atan2 entPos.y - otherPos.y, entPos.x - otherPos.x
  vel = 30
  velX = vel * Math.cos direction
  velY = vel * Math.sin direction
  entBlob.velX += (velX-entBlob.velX)/10
  entBlob.velY += (velY-entBlob.velY)/10
  otherBlob.velX += (-velX-otherBlob.velX)/10
  otherBlob.velY += (-velY-otherBlob.velY)/10

BlobSystem =
  priority: 1500
