The feud is on. Dennis Coles, a rapper better known by his stage-name “Ghostface Killah,” a member of the Wu-Tang Clan, released a video Tuesday in which he insults and attempts to shame the former pharmaceutical executive Martin Shkreli. The nearly 12-minute clip represents the latest volley in a battle that has been publicly playing out between the two over the past couple of months. “You a fake ass supervillain,” Killah says, showing clips of baddies from the Batman live action TV series from the ’60s.