Crossbone Gundam: Skullheart summary: Sequel to Crossbone gundam. Unlike the other two episodes of the "crossbone saga" this volume focuses on several short stories that don't have such a great effect over the jupiter war. While the book itself is not meant to be comedy, but the "character" of the stories is (generally) much less serious than either the first or the third part of the crossbone series. The stories are pretty varied in both, placing and characters. Due to that the series is actually decently strong in the cameo department.