MARCH 18 & 19 Her surprise Danforth Music Hall gig last November was just an appetizer; Rihanna serves up the main course over two arena-filling mega-shows. The fiery singer’s Diamonds World Tour is in support of her chart-topping album, Unapologetic. Air Canada Centre, 7:30 p.m., $68.75 to $163.75; call 1-855-985-5000 or visit Ticketmaster to buy. —Anna Marszalek