The Avengers may have gained a canine companion after a dog from a family in North Carolina gave birth to a bright green puppy, which they named the Hulk.

Gypsy, a white shepherd owned by Haywood County resident Shana Stamey, gave birth to eight puppies last week.

Her three-hour job went smoothly until the fourth pup emerged – in the form of a small but mighty tuft of lime-green fur.

“I started to panic,” Stamey told the media.

“But everyone was in good health.”

Experts said there was a normal explanation for the puppy’s coloring – and no, he wasn’t exposed to any gamma rays.

Fluid from Gypsy’s stomach likely stained the white bitch’s fur during pregnancy, said Suzanne Cianciulli, director of Junaluska Animal Hospital in Waynesville.

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Gypsy’s regular baths and daily licks should tone down the Hulk’s green tint in a few weeks, Stamey said.

However, the puppy’s new superpower, which the family considers an “aggressive appetite”, will likely remain.

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