Dream Town Hall
The Town Hall is a location in Animal Crossing: Wild World, Animal Crossing: City Folk and Animal Crossing: New Leaf, which serves as the building where most of the town's civic duties are carried out. Among them are the Public Works Projects, which allow the option for the Town Hall to be remodeled. In New Leaf, the Town Hall can be one of four different colors upon starting a new save file. The one appearing in the final smash, as well as Isabelle's on-screen appearance, appears to be based on the coloration and appearance of the original town halls in Wild World and City Folk.
Isabelle's Final Smash is a trapping-type Final Smash. If she is next to an enemy fighter, Isabelle will have Tom Nook and his nephews, Timmy & Tommy, build a Town Hall around the opponent. After the Town Hall is completed, they cheer before it is blown up. The explosion launches the trapped victim (and any other opponents close enough), briefly knocks over Isabelle (much to her shock), and sends the three tanukis flying. While nearly identical in function to Villager's Final Smash (Dream Home), Isabelle's variant deals 5% more damage during construction, thus KOing 5% earlier.