K.O. Beast (actually, the title I saw it released as is K.O. Century Beast, but I didn't see a way to put that in there) is an anime you'll either like or absolutely loathe. The summary is a bit off as well; in the past, the earth was split into two hemispheres. In the north evolved the beasts, and in the south, humans still thrived. However, a problem with the split causes the hemispheres to reunite, causing confict between the beasts and the humans.