Several harlequins are in the service of Duke Prosper de Montfort. When Hawke and Tallis attempt to escape the Vaults by backtracking through Chateau Haine proper rather than fleeing through the Retreat, they are confronted by the Duke and a squadron of chevaliers. After Cahir leaves, a Harlequin will appear to lead the troops. Another Harlequin leads a group of soldier who attack Hawke as they attempt to return to The Dungeons.
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A Harlequin is seen protecting the Grand Apartments from spies in the Winter Palace during the grand ball, this apparently entails murdering elven servants. The Inquisitor will encounter at least two of them while completing the quest: one can be found in the Grand Apartments with a large group of Venatori, another will be found about to murder an elven woman and be kicked out the window by the Inquisitor. More can be found protecting Duchess Florianne if she is violently confronted.