Wizards of the Coast is celebrating "D&D's" 50th anniversary with new books, including a rework of its Dungeon Master's Guide.Esther Derksen via Getty Images; WOTC"Dungeons & Dragons" is now a 50-year-old game.It's undergoing a major facelift, with new core rulebooks being released through next year.BI spoke to a Wizards of the Coast executive to hear how the company is trying to keep "D&D" hot.For half a century, the game of "Dungeons & Dragons" has been a cornerstone of the nerdy experience.The tabletop game allows people to tell stories in groups, with turns of the narrative being decided by the roll of a 20-side die.