From the introduction:
In the Junkyard, there is only war. Oh sure, there may be small islands of peace, really stalemates, in this sea of conflict, but they are just that. There is no sun here, no stars, no rain or flowers. There is no nature, there are no children, only a eternal war between the six tribes: the two smallest ones, the Embryon and the Vanguards, the two tribes competing in the middleweight league, the Maribel and Solids, and finally the largest and strongest ones, the Wolves and the Brutes. Each with their own leader, who commands the obedience and loyalty of his or her tribe. Not to say betrayal is impossible, of course...