Vikings is back -- and fiercer than ever!

After Ragnar's (Travis Fimmel) death last season, it's anyone's game, and Ivar (Alex Høgh Andersen) knows it.

Only ET has an exclusive season five teaser trailer, in which Ivar prepares for the show's biggest "war" yet.

"There is going to be a war -- a war against Lagertha, who killed my mother in order to be queen. And, of course, a war between brothers," he says in the clip, as his blood-spattered face turns into a grin.

WATCH: Comic-Con: 'Vikings' Season 5 Trailer Shows the Epic Consequences of Ragnar's Death

"You have a choice. Fight alongside me, or I will kill you," he offers, but it's Lagertha (Katheryn Winnick) who delivers the teaser's chilling last line: "Now I can die."

Watch the epic trailer in the video player above.

ET spoke with Andersen last year, who teased that his character would only become more out of control after killing his brother at the end of season four.

"Despite all the experience he has gained, he has become more of a man, definitely, but still struggles with that little kid inside of him that is just so angry, so hurt," he said. "He's completely out of touch with reality and his emotions."

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Vikings returns Wednesday, Nov. 29 at 9 p.m. ET/PT on History.

Get caught up on last season in the video below.