Russians have used hypersonic missiles before (for example, Kinzhal, which is actually modified Iskander, hypersonic speed is achieved because of air launching with supersonic starting speed) and Ukrainians even managed to shot them down with Patriots. New thing is use of longer range ballistic missile with MIRV (Multiple independently targetable reentry vehicle) payload. Usually these are used only with nuclear warheads and so far no other country has ever used them in actual war.