The Atlanta Dream has to play its Finals home games at the Arena at Gwinnett Center, about a half hour outside of Atlanta, because Philips Arena is hosting Disney on Ice.
From the local NBC site:
ATLANTA — The WNBA Finals will be played at the Arena at Gwinnett Center when the Atlanta Dream hosts its portion of the best-of-five series, reports the Gwinnett Daily Post.
The Dream's usual home, Philips Arena, isn't available for the WNBA Finals because it has "Disney on Ice: Let's Celebrate!" in town, the paper reports.
Disney on Ice: Let's Celebrate is described as "one colossal party on ice, with all your favorite Disney friends" that involves "a winter wonderland with Mickey Mouse and Minnie Mouse, a Halloween haunt with the Disney Villains", and other Disney-themed iceskating scenarios.