The Patternists’ strategy was to concentrate on the upper slopes and the landslide’s rubble, a marginal niche where they hoped to excel. Their cold crater in Syrtis Major had given them some expertise in alpine species, and they hoped to exploit this strength. The landslide’s long slope, far above sea level, was to be their power base. The crawler lurched downslope, blasting out a fine spray of lichenophagous bacteria.