Yeah... I can actually solo these without too much hastle, but apparently they link from the sky. One was following me on the ground, I ran near another one and it started following me from the air, and only landed when it got to the tunnel. As you can see here, they both wandered off as I died, and one took flight again as soon as it was out of the tunnel.
It's all fun and games until someone loses a soul... wait!!! You're a blu, allright! Our souls are long gone. lol @ the mob, it looks all bummed out and slouched over like he just checked the fridge and it was empty. Look how skinny he it is. /laugh