Ah thanks. I've walked straight up to that thing but I didn't think to try the device. There are like 6 routes being blocked by obnoxious npc abuse so it's hard to tell sometimes what opened up.Did Achroma/Akuroma/Corless hand you a key item?Anyone know what to do after you catch terrakion and beat the 8th gym. I keep looking for guides but it's still kind of early besides sitting through long youtube videos that turn out to be wrong. I'm guessing there's some plasma scene before whatever victory road I go to.
Go to the cave north of Undella Bay by surfing, there is an East exit blocked by astoneCrustle like on Route 4, the key item should let you pass.