'Game of Thrones': Who's Ahead Going in to Episode 6?

Will Littlefinger or Daenerys prove to be the world's most unstoppable force?

Game of Thrones shook up the chessboard in last Sunday's episode with a big reveal dating back to the series' pilot.

Major deaths withstanding, no episode has been a game-changer in quite the same way, with the revelation that Littlefinger was behind Jon Arryn's murder. There are plenty of questions to be answered in Sunday's episode. Is Littlefinger unstoppable? Will Daenerys' stop in the East prove fruitful or fatal?

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Here we break it all down.

1. Littlefinger (+3 from previous rankings)

Lord Baelish (Aidan Gillen) had a huge episode. His power grows. He's now married to Lysa (Kate Dickie), making him Lord Protector of the Vale. His master plan remains unknown, but one thing is for certain: he wants it all.

Key line: "Know your strengths. Use them wisely, and one man can be worth 10,000."

2. Daenerys (+1 from the previous rankings)

Dany (Emilia Clarke) already has enough men and ships to make a serious go at the Iron Throne. Instead, she's decided to remain and rule in Slaver's Bay (for the time being.) This grants her time for her dragons to grow and for her to learn how to govern. Perhaps she can conquer a city or two in her downtime. The risk? Tywin is now wary of her growing power, according to the trailer for the next episode. He could make moves to check her.

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Key line: "I will do what queens do. I will rule."

3. Lady Olenna/Margaery (-1 from previous rankings)

The power tandem is still going strong, with Margaery (Natalie Dormer) poised to be the next queen of the Seven Kingdoms. The only reason for their fall in this week's rankings is that some of their strength is derived from their alliance with Littlefinger — proven once again to be a fickle ally at best.

Key line: "We may be faced with an alarming number of weddings soon. I won't even know what to call you. Sister – or mother?"

4. Tywin (-3 from previous rankings)

Tywin is working on his alliances with the Tyrells and Dorne – a prudent move. But on the other hand, the Tyrells murdered his grandson Joffrey. And the crown owes a tremendous amount of money to the Iron Bank of Braavos. It's a tenuous situation, with Tywin a few false steps away from toppling.

Key line: "You don't need to make formal alliances with people you trust."

5. Cersei (+1 from previous rankings)

Cersei (Lena Headey) played the game better this week. She is aligning herself more closely with Tywin and even striking up something of an understanding with Oberyn, one of the men with the power to convict Tyrion of Joffrey's murder. Seeing Tyrion's head on a spike is all she really wants now.

Key line: "What good is power if you cannot protect the ones you love?

6. Oberyn (-1 from previous rankings)

The Prince of Dorne (Pedro Pascal) is still in a great position, but he made no moves to improve his standing this week. Still, if he wants revenge on the Mountain, he's in the right place. And cozying up to Cersei — also out for revenge — is a smart move. She is resourceful and may be able to get him in a room with the Mountain.

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Key line: "I can't say it without turning sad. And after I turn sad, I grow angry."

7. Jon Snow (newcomer to the rankings)

Lord Snow (Kit Harington) proved his leadership abilities once again by slaughtering the horrible mutineers at Craster's Keep. Some of his higher-ups at The Wall expected it to be a suicide mission. When he returns to Castle Black, Jon will be in his best position ever to potentially become the next Lord Commander. Bonus: he's got his direwolf back!

Key line: "Where in Seven Hells? Come here!"

8. Sansa (newcomer)

Sansa (Sophie Turner) is forever a pawn of the powerful. After escaping the Lannisters she finds herself in the clutches of her aunt, who wavers between accusing her of lusting for Littlefinger and attempting to marry her off to young Robin. She's just one bad Lysa moodswing away from being thrown out the moon door.

Key line: "All he says is I'm stupid. I'm a stupid little girl with stupid dreams who never learns."

9. Tyrion (no change)

Tyrion didn't pop up in this episode, but his situation is hardly improved. Still imprisoned, he is set to be tried by a jury that includes his father, obviously not his biggest fan, and Oberyn, who is growing more fond of Cersei, also not a fan.

Whom do you think will reign supreme in this Sunday's Game of Thrones? Let us know in the comments, and check THR.com/GoT Sunday, when director Alik Sakharov will share his thoughts on the episode. (He's already released a few tidbits here.)

Game of Thrones airs Sundays at 9 p.m. on HBO.

Email: Aaron.Couch@THR.com
Twitter: @AaronCouch