The Reckoning
An event (see: Timeline) which takes place shortly after the campaign The Sword of Frost from Heroes Chronicles (precisely on 08-04-1177), a massive explosion created by the clash of Gelu's Armageddon's Blade and Kilgor's Sword of Frost. It starts a chain of thousands of earthquakes and volcano eruptions, which in turn destroy the planet itself. However, portals open and many people escape from the dying world helped by the Angels.