It's been a long journey since its beginning but now it seems the Westeros land will have one of those definitory battles for supremacy. The Iron Throne has been providing the illusion of power and control in most of the character's minds. With those thoughts nestled deep down inside their minds, the tension has now reached the boiling point. The first three episodes of the Season 7 did nothing but to cement some freshly created alliances. While in the South Cersei brought Euron as her new loyal ally and possible future husband, going north and you'll find a new mixture getting shape at Dragonstone.
The rightful heir to the Iron Throne and the last living of Targaryen dynasty, Daenerys built the foundation of her partnership with Jon Snow, the King of the North.
War is imminent and will do nothing but to bring weakness among the living while the White Walkers are marching to the Wall
The official preview of the Season 7 Episode 4 may give some small clues about what is going to happen next. By the end of Episode 3, it became clear that Cersei Lannister will use every bit of her influence and power to gather just enough support to keep her hands on the Iron Throne. Trying to stay close to his twin sister and mistress, Jaime Lannister let the Unsullied led by the Grey Worm to capture Casterly Rock (Lannister's home castle) as a decoy just to win the upper hand to follow his brilliant strategy.
Jaime did something unexpected by attacking House Tyrell in Highgarden with a sole crucial objective- its gold that will help Cersei's negotiation with the Iron Bank.
The official preview ends with the image of a dragon flying up in the sky (probably Drogon) suggesting that Daenerys Targaryen will use her secret weapons just enough to balance the equation.
As Euron Greyjoy destroyed her fleet, she lost any leverage she had on the Narrow Sea dispute.
Arya, Sansa and Brann Stark the subject of a highly-anticipated reunion at Winterfell
The last offshoots of House Stark could finally hope for a complete reunion after having such sinuous routes. Sansa and Brann Stark regrouped in Winterfell while Arya is nearby.
Their highly-expected reunion will provide the proper chance to make an assessment of how much they changed since the beginning. Bran is no longer a simple crippled as he assumed the role of the Three-eyed raven. Arya has mastered the Many-Faced God's craft while the older sister Sansa Stark seems to have become a true leader of Winterfell.