I haven't installed the Beta for 1.29, but I thought I'd share this for Frogboy's benefit in case he's watching.
I sent some scouts into the backfield of my nearby ally to explore what is back there, and this is what I found...
http://imgur.com/3XSjn2a
Essentially what we have is multiple stacks of Pioneer armies huddled around a settle-able spot, a crystal crag, and an earth shard. Looks like ALL the factions have been sending Pioneers here to try and grab it, and my best guess is that either the Dragon has been killing them all, or they're staying a respectable distance away from the Dragon.
My biggest question though is why the AI is concentrating on building so many Pioneers to accomplish this?