Game Of Thrones: 10 Most Powerful People Going Into Season 6

3. Olenna Tyrell

Olenna Tyrell is an insane character and a tremendously curt player of the game. She's utterly fearless and let's face it, she couldn't care less what any man, woman, peasant or ruler makes of her. That's what makes her such a powerful figure, in addition to her famous surname, paradise homeland, and cunning mind. Her threats about cutting off food supplies to King's Landing could destroy the capital if she went through with the plan, meaning she's effectively got the Lannisters in a headlock. The only negative on her scorecard at the moment is that Margaery and Loras are imprisoned and the future doesn't look bright for them. Olenna can function without them, but obviously King's Landing would be a far more menacing place without her grandchildren in positions of power.