Ivan's nickname, the Terrible (Грозный), is closely related to "гроза", meaning "thunder". I guess that sword is a reference to that?

worldendDominator said:

Ivan's nickname, the Terrible (Грозный), is closely related to "гроза", meaning "thunder". I guess that sword is a reference to that?

Yes. In fact, that nickname is (somehow) translated into Japanese as "雷帝" (raitei; 雷=thunder, 帝=emperor).