The Duel in the Asgardian Palace was an open confrontation between Thor and Hela.
Thor, Valkyrie, and Bruce Banner arrived to Asgard in the Commodore. Thor informs them that a man on the ground in Asgard, referring to Heimdall and the plan they have agreed. Heimdall tells the Asgardians that Hela has arrived at the fortress and begins to evacuate them. Hela then breaks down the doors to the refuge.
Meanwhile, Thor gives Valkyrie her former outfit to wear into battle. Thor goes to the throne room of Asgard and takes his seat there, awaiting Hela. Hela breaks down the doors to the refuge, as the Asgardians use the opportunity to cross the Bifrost Bridge, hoping to escape.