With the tragic news that Dame Diana Rigg died Thursday at age 82, those who knew the British screen legend best reacted to the loss. The acclaimed Royal Shakespeare Company stage actress and star of The Avengers TV series and died peacefully in her sleep after being diagnosed with cancer in March. But she's probably best known to modern viewers for her portrayal of Olenna Tyrell on Game of Thrones. HBO's official Twitter account posted a message reflecting on the Queen of Thorns' many memorable lines: "Be a dragon. The realm will always remember Diana Rigg."

In addition, costar Nikolaj Coster-Waldau (who played Jaime Lannister in the series) tweeted: "Dame Diana Rigg. She always raised the bar with her incredible talent, intelligence and wit. An absolute joy and honor to work with. May her soul Rest In Peace."

John Bradley (Samwell Tarley) wrote: "Diana Rigg was just wonderful. But you all knew that already. Everybody did. Very sad news."

Liam Cunningham (Davos Seaworth) wrote: "Rest in peace. A remarkable wonderful and enormously talented human being."

Pedro Pascal (Oberyn Martell) wrote: "The true queen of Westeros."

Mark Gatiss (Tycho Nestoris) wrote: "It was my great joy and privilege to have known Diana Rigg. From three slightly hysterical months at the Old Vic in ‘All About Mother’ to writing The Crimson Horror for Diana and her wonderful daughter Rachael. Flinty, fearless, fabulous. There will never be another. RIP."

In addition, from outside the GoT family:

Samuel West (actor): "Very sad to hear that Diana Rigg has left the stage. An honour to work with her. I think #AllCreaturesGreatAndSmall was her final screen job; she made a fabulous Mrs Pumphrey. Doesn’t really make sense to think of her having died. She generally lived the hell out of everyone."

Edgar Wright (director): "What to say about Diana Rigg? I could talk about her incredible career, but for now I'll just say as a lifelong fan, it was beyond a thrill to work with her on her final film. She exceeded all my highest expectations, so blazingly talented, fiery & funny. Miss you already Dame D."

Rachael Stirling (Daughter): “My Beloved Ma died peacefully in her sleep early this morning, at home, surrounded by family. She died of cancer diagnosed in March, and spent her last months joyfully reflecting on her extraordinary life, full of love, laughter and a deep pride in her profession. I will miss her beyond words.”

Sir David Hare (playwright): “Diana Rigg had a dazzling change of direction in middle age as a great classical actor. When Emma Peel played Euripides’ Medea, Albee’s Martha and Brecht’s Mother Courage she swept all before her.”

Jonathan Kent (theatre director): “Diana Rigg’s combination of force of personality, beauty, courage and sheer emotional power, made her a great classical actress - one of an astonishing generation of British stage performers. I was so fortunate to direct her in a series of great classical roles - Medea, Phèdre - in Ted Hughes’ version, specially written for her - Mother Courage and Dryden’s Cleopatra. Her dazzling wit and that inimitable voice made her an unforgettable leading figure in British theatre.”

Sir Tom Stoppard (playwright): “For half her life Diana was the most beautiful woman in the room, but she was what used to be called a Trouper.  She went to work with her sleeves rolled up and a smile for everyone.  Her talent was luminous."

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