Crawler Spawning

[Magoober]

When i'm playing a defense mission, there's always this stupid crawler chilling at the other side of the map. I was thinking that there should be little holes around the map that are closer to the area the defense is, so you don't have to travel across the map to kill the Tiny Tim holding up the mission. The crawlers could "crawl" out of these holes and spawn closer to the main area and would seem more natural.