Proto-Martians

Roughly, proto-martians on Mars are to Martians what Neanderthals are to Humans.

Description
After the Martians died out due to the plague, the proto-martians ascended to become the new top of the crop. These creatures are somewhat intelligent and can clearly battle their foes with a tactic in mind. They also show signs of civilization by living in villages and using tools and weapons. However, they can't be reasoned with and take great delight in slaughtering their enemies with their crude wepaons, showing no mercy.

Proto-martians have spread over the planet since the disappearance of the higher Martians, becoming a serious threat.