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Wolverine's next appearance was in 1975's Giant-Size X-Men # 1, written by Wein and penciled by Dave Cockrum, in which Wolverine is recruited for a new squad.

Gil Kane illustrated the cover artwork but incorrectly drew Wolverine's mask with larger headpieces.

Dave Cockrum liked Kane's accidental alteration ( believing it to be similar to Batman's mask ) and incorporated it into his own artwork for the actual story.

Cockrum was also the first artist to draw Wolverine without his mask, and the distinctive hairstyle became a trademark of the character.