Actually, based off of a Google search, the true spelling of the word is 'metalify'. I've also seen it hyphenated so that it appears as 'metal-ify'. Regardless, it's a slang term and doesn't have a correct spelling. It's like comparing other slang words with variable spelling including but not limited to variations of 'faggot', also seen as 'faget' or 'fagot' and 'beotch' also seen as 'biotch'.