The term 'Down Under Critter' refers to three animals native to Australia: the Roo (3 letters), KOALA (5 letters) and EMU (3 letters). The Roo is a marsupial mammal, also known as a kangaroo, that is found in Australia and New Guinea. The KOALA is a tree-dwelling marsupial that is native to Australia and feeds on eucalyptus leaves. The EMU is a large flightless bird that is the second-largest living bird by height. All three of these animals are iconic symbols of Australia and are commonly referred to as Down Under Critters.