Here it is the new trailer of season 4.
From what we know from the IGN interview and the panel:
We find out that there will be more episodes how many maybe 20 not for sure.
There will be a clash between Rollo and Ragnar but will it be a clash?
Bjorn will find out his wife has left and maybe some burial Travis could tease us.
Bjorn will more and more stand on his own and will become mates with Ragnar.
The child of princess Kwindreth is his.
There will be more love triangles.
Rollo needs to get the French on his site with first of all a language problem.
Period of the Vikings this season will be the Golden Age.
Ragnar will have another love.
King Eckbert want to succeed in the plan to become king of all kings.
There will be a new romance for Bjorn.
Ragnar will become more and more intrigued by death.
What do we see in the trailer
We see Bjorn take the lead to tell them who is the king.
Rollo getting married. Our French Romance is in the air although did she try to kill him at the end of the trailer? Will he betray Ragnar or will he stay loyal to Ragnar. I do think Rollo will kill a squad of Vikings but that is only to get Ragnar to him I think. If Ragnar is not there he want it to get Ragnar to Paris.
Ubbe and Hvitserk are sure growing up to learn from Bjorn. We don't see Ivar in the trailer yet. Will the brothers go and raid England or somewhere else?
Aslaug who wants to know if a woman will succeed in Kattegat. Will she get an answer from the seer? and would she like the answer. I am not sure but if she got smashed to the ground by Ragnar I wonder.
Lagertha will get her revenge on Einar but will she have it also on Kalf? Or does she love Kalf too much to get her revenge just jet.
The arrest of Floki the humiliation and the downfall what I can say about this that it looks like he is still familiar with the god Loki. Although I couldn't see it for sure in the trailer. Because Loki was on a rock not bound inside a cave and I saw no snake although he screamed. Loki his chains were made of his children. Would they kill Helga and Angrboa? Will we see Floki die or is this just a test, and will he survive this test?
To end with the seer "If the fans knew what was coming in S4, they would be dancing naked in the halls"