WARNING: The following contains spoilers for Justice League: Endless Winter #2, by Andy Lanning, Ron Marz, Carmine Di Giandomenico, Howard Porter, Hi-Fi and Andworld Design, on sale now.

As a threat that first menaced the DC Universe during the Viking Age, the Frost King prompted an ancient iteration of Swamp Thing to rise up and join the impromptu Justice League of the era to take him down. And as the crossover event "Endless Winter" nears its end with the Frost King resurfaces in the present of the DCU more powerful than ever, Swamp Thing unveils his own upgraded new transformation to take the fight directly to the arctic antagonist by combining the powers of the Green with another familiar DC superhero: Viking Prince.

Flashbacks revealed that the Viking Prince paid the ultimate price to help defeat the Frost King during the Viking Age. The warrior's heroic sacrifice came in the wake of the Viking Age's Swamp Thing being killed by the supervillain, with the Frost King summoning a magical blizzard to affect and weaken the Green before destroying the Parliament of Trees' avatar. With his last breath, the mortally wounded Viking Prince fought the Frost King as a glacier fell on top of them, imprisoning the supervillain for centuries before the Kryptonian crystals from the Fortress of Solitude inadvertently empowered him deep within the ice and facilitated his escape after being unearthed by the nefarious Stagg Industries.

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Swamp Thing Frost King Endless Winter

While Black Adam battles the Frost King before the supervillain can complete his plot to plunge the Earth into a perpetual, magical blizzard, the heroes undergo their own magical ritual to summon a defender capable of defeating him, even with his Kryptonian enhancements. Doctor Fate performs an occult ceremony that raises the Viking Prince's soul and temporarily bonds it to the Green. Now merged with all the powers of Swamp Thing, the merged superhero now sports bark armor resembling the Norse warrior's usual regalia as he grows to kaiju size and heads to the arctic circle just in time to confront the Frost King for a rematch as he similarly grows to the size of a behemoth.

As the two titans engage in their colossal rematch, the other heroes discover that the frozen kaiju is just an icy avatar for the Frost King. The actual villain is still in his human form, nestled deep within magical ice within the glacier. While Black Adam moves to kill the villain after discovering his vulnerable true form, he is stopped by Superman while the Frost King's avatar is defeated and the Justice League helps reform the remorseful foe after reuniting him with his family. With the polar threat neutralized, the Viking Prince's soul is laid to rest in Valhalla once more as this vision of Swamp Thing is returned to the Green.

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Swamp Thing Frost King 2

With the avatars of the Green able to draw power from all past Swamp Things through their shared connection to the Parliament of Trees, this may not be the last time the Viking Prince Swamp Thing is seen. Alec Holland has teamed up with other past incarnations of the avatar before and while the Viking Prince was bonded to the Green by Doctor Fate rather than the Parliament of Trees, this titanic avatar had just an apparent connection to the Green as any of his counterparts. With a new Swamp Thing coming in "Infinite Frontier", the latest avatar joins a host of that includes now not one but two different Swamp Things linked to the Viking Age.

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