It’s an all-out family war on Vikings.

The History Channel drama returns for the second half of season four later this year and during Friday’s Comic-Con panel, the cable network debuted the brand new (and super intense!) trailer previewing the chaos that’s about to come.

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Years after disappearing, Ragnar (Travis Fimmel) returns home a hated man, challenging his sons to kill him if they wish to take the throne as king.

“My father has returned. Perhaps he should not have come back,” Ragnar’s eldest son, Bjorn (Alexander Ludwig), forewarns.

Others anticipate Ragnar’s re-emergence will bring “calamity, chaos, tragedy and death,” but Bjorn promises he’s ready to fight to the death: “I am not afraid.”

As both sides prepare for the biggest battle the show has likely seen, a montage of the dramatic and violent lead-up can only lead to one conclusion: The world is about to be brought to its knees.

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As the ruthless King Ecbert of Essex (Linus Roache) ominously predicts in the two-minute trailer: “This is the time of war.”

To watch the rest of the intense new season four trailer, press play on the video above!

Vikings returns this fall on History Channel.