Barnacle is a fictional mutant

Mutant (Marvel Comics)

In comic books published by Marvel Comics, a mutant is an organism who possesses a genetic trait called an X-gene that allows the mutant to naturally develop superhuman powers and abilities...

 from Marvel Comics

Marvel Comics

Marvel Worldwide, Inc., commonly referred to as Marvel Comics and formerly Marvel Publishing, Inc. and Marvel Comics Group, is an American company that publishes comic books and related media...

 who first appeared in X-Men: Magneto War #1.

Fictional character biography

Barnacle is one of the newer Acolytes

Acolytes (comics)

The Acolytes is a team of comic book mutant supervillains in the Marvel Comics universe. The Acolytes followed the principles of the mutant Magneto, particularly the mutant right of superiority over normal humans. Some members of the Acolytes even worshipped him with a religious fervor and regarded...

 that debuted during the Magneto War.

He was killed in action during the Sentinel attack on Genosha

Genosha

Genosha is a fictional country that has appeared in numerous comic book series published by Marvel Comics. It is an island nation that exists in Marvel's main shared universe, known as "Earth 616" in the Marvel Universe. The fictional nation served as an allegory for slavery and later for South...

.

During the Necrosha event, he, along with several other Acolytes, is resurrected by Eli Bard in a mass resurrection on the island.

Powers and abilities

Barnacle has the mutant ability to solidify the moisture secreted by the human body as well as create an indestructible armor on his skin, trap others in a restricting shell and release a stream of hardened biomatter.