Truth be told, this was one of the reasons Savage Worlds appealed to me some years back.
From the description:
In Dawn of the Daikaiju, players take on the roles of giant monsters called kaiju or daikaiju (the terms are used interchangeably and both mean “giant monster”). Though daikaiju range in origin from oversized insects and dinosaurs to bio-engineered alien weapons, they somehow recognize in each other a single species. Even daikaiju from different worlds work together in packs.
Dawn of the Daikaiju contains a Plot Point Campaign, Adventure Generator, specially adapted race creation rules, and new Edges and Hindrances—and it’s all in Kaiju Scale!
I mean, c’mon, who wouldn’t wanna try to play tabletop Rampage, huh?
Don’t touch that dial!