Grindcore, following in the steps of thrash, is a hybrid between hardcore punk and the heavy metal of the time. It is recognized by its fast chromatic riffing, punk style song formats, blast beats, heavily emotional and social protest orientation, and hoarse vocals like those of death metal. Grindcore was invented by Repulsion, refined by Napalm Death, Terrorizer and Carcass, evolved by Bolt Thrower and Godflesh, and now exists in a modern form perched precariously between metalcore and nu-tek-deth.