Planet looters are a race of aliens that have run out of something, and must steal it from others. Frequently, from us here on Earth. This is a bit peculiar in that their demonstrated level of technology makes one wonder why they'd target Earth when it would be far easier to find an uninhabited planet and strip-mine that. Another way around the question is to make Earth's abundant ecosystems and temperate climates the resource, and the aliens view primitive humans as unworthy pests infesting an ideal new home or vacation spot. Examples of Planet Looters include: