Nick Cannon is back! After having to sit out most of the season, the longtime host is stepping back into his glittery hosting loafers to helm an exciting new episode and to reveal his shiny clue cannon.In this exclusive clip from Wednesday's Group A Finals, Cannon reveals his own cannon — specially, an air-powered t-shirt cannon that he uses to fire clues up to the panel of celebrity sleuths.The host unveils his hint delivery system following a new performance from The Russian Dolls — the show's