Get off my lawn

Space Age, on Vulcanus. Disturb a demolisher by building on its territory. Each demolisher patrols a marked patch of ground; place any building inside one of those territories and the resident sandworm surfaces, furious. Pops the first time you provoke one - which you'll do just trying to expand on Vulcanus. Leads straight into fighting them, If it bleeds, we can kill it.