Players in the new season of Bravo’s “Celebrity Poker Showdown” include Alex Trebek, Rosie O’Donnell, Meatloaf and Omarosa Manigault-Stallworth, the network said Thursday. The new season, beginning Aug. 18, features six two-hour episodes, including theme nights such as Reality All Stars and Ladies Night. In all 25 celebrities compete to win $250,00 for charity. The show is hosted by Dave Foley and poker pro Phil Gordon.