Batman Gets Help to Defeat a Zombie Army in Justice League Action Clip

Batman needs help in this clip from "Justice League Action," and the magic-powered Zatanna and Constantine are the only heroes who he can turn to to team with himself and Swamp Thing. Solomon Grundy has obtained a mystic gem, granting himself the ability to raise a zombie army, and it's going to take more than a few gadgets from his Bat-belt to take it down.

Written by Paul Dini, the episode not only brings an animated Swamp Thing to the Justice League for the first time, it reunites Kevin Conroy and Mark Hamill, This time, however, they're a team rather than adversaries, as Hamill takes break from voicing the Joker in order to bring Swamp Thing to life in the episode.

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“Zombie King” arrives Saturday, February 4 at 7:30 a.m. on Cartoon Network. You can check out screenshots from the episode and Cartoon Network's official description below.

When Grundy escapes his Louisiana prison, intent on using a magical crystal to raise an army of the dead from their graves, only Batman and Swamp Thing (voiced by Mark Hamill) stand in the way of his growing zombie army.

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