Ms. Mari takes Lan and some of the other kids on a field trip to the ancient Yokayoka Hot Springs, but Lan finds more fun NetBattling a local employee named Tamako. That is, until he discovers Tamako and her NetNavi HeavyMetalMan are so obsessed with NetBattling they won't let Lan do anything else. Even worse, the goofiest villain on the Net, BubbleMan, has returned to get his revenge on MegaMan and Lan, even if it takes opening a Dimensional Area to do it!