Cersei Lannister has had one of the craziest journeys of any of the characters on Game of Thrones, and it's hard to imagine the show without her shady shenanigans in King's Landing. Still, her arc at this point seems like it will only have one logical conclusion: some kind of epic death by the finale. Actress Lena Headey has some ideas about who should get to the do killing. According to Headey, either Tyrion or Arya should get the honors of ending Cersei for good.
In the aftermath of the Season 6 finale that saw Cersei go full villainess and ascend to the Iron Throne, Lena Headey revealed her picks for who should kill Cersei in a chat with EW. Considering that Arya has already made her merry murdering way back to Westeros and Tyrion is on his way with Dany and her dragons, Cersei is going to be in more danger from both of them in Season 7. They both have some serious bones to pick with the current ruling queen of the Seven Kingdoms.
Arya has had Cersei on her kill list ever since she started naming the names of people who deserved to die, and Arya has spent most of her time over the past couple of seasons ticking people off of her list and training to be an assassin. She already used her assassin training once in Westeros to kill Walder Frey (who hosted the Red Wedding); Cersei is the biggest name left on her list, and it wouldn't be a huge surprise if Arya chose her for her next target. Ned may have died all the way back when Arya was still an adorable ragamuffin in Season 1, but she's a Northerner, and Northerners never forget. Arya may bring a reckoning down on Cersei in the not-too-distant future. Lena Headey won't have worked with Maisie Williams since their characters went their very separate ways at the end of Season 1; their reunion onscreen could be Cersei's death.
That said, Tyrion would probably get more satisfaction out of killing Cersei. Arya is ticking names off of a list that she started only a few years ago; Tyrion endured a lifetime of torment courtesy of his older sister, and he has her to thank for being named Joffrey's murderer. In fact, Lena Headey thinks that Tyrion would enjoy her death more than anybody else. She had this to say about the possibility of Tyrion enacting vengeance on Cersei:
Lena Headey and Peter Dinklage would undoubtedly be fantastic in a scene about Tyrion killing Cersei. Their interactions were some of the most compelling and entertaining during Tyrion's brief stint as Hand of the King, and the poetic justice of the Imp killing the Queen after everything they've put each other through over the years could be perfect.
Personally, I'd have to vote for Tyrion out of Lena Headey's two candidates for Cersei's killer. So much of what the Lannisters have done during Game of Thrones has been in the name of preserving their house; Tyrion or even Jaime killing Cersei could see the end of House Lannister as a major player in the Seven Kingdoms. After what the Lannisters have done - whether directly or indirectly - to Houses Baratheon, Stark, Arryn, Tully, and Martell, a dissolution due to in-fighting could be the closest thing that Game of Thrones could possibly deliver as a happy ending.
Unfortunately, Season 6 has only just come to an end, and we'll have to wait a while to see if Arya or Tyrion will make a play on Cersei. Take a look at our breakdown of what we know so far about Game of Thrones Season 7 for a peek at what's to come, and check out our list of prospective Thrones spinoffs to get your imagination going.