After mounting Toothless's head on the wall, Hiccup becomes the new chief of Berk. He has Valka assassinated for her controversial views on the Vietnam War. Cloudjumper starts a mafia, and a gang war starts between him and Snotlout, and ends up killed by his lover Meatlug. Fishlegs moves to Chicago and becomes a famed radio news host. After the gang war, Tuffnut and Snotlout get married, and the two start a nightclub, where their most profitable dancer, Gobber, entertains. Eret comes to assassinate Gobber,(orders from Hiccup) but falls in love with him instead. They get married and both form a dancing duo. After her divorce with Hiccup, Astrid moves to Spain to become a famous painter. Ruffnut becomes a real estate agent and ends up selling part of Berk to Dagur. Hiccup declares a war between the two tribes, and tries to take over Germany. He is then exiled by his own people when he loses his sanity. Hiccup, now a madman, finds himself on a remote island, where he dies of starvation. Tuff and Snotlout move to New York to continue their business, and Ruffnut becomes Dagur's wife. Dagur becomes the chief of the two tribes, and manages to get the Outcast to join. As for Drago, he becomes a journalist and moves to Maine, and changes his name to Bob Kennith.

That's exactly what happens.

Someone dies.

No and yes, respectively.