Shenseea Turns Heads as Mantis From 'Guardians of the Galaxy' for Halloween - DancehallMag. Of all the characters in the Marvel universe, Shenseea went with the soft-spoken empath with antennae. The Jamaican star marked Halloween by transforming. DancehallMag is an independent news outlet that covers all things Dancehall and Reggae music, the artists, and culture.