From the Super Mario Wiki
Underground Gossip is a level in the Lava Lair in the Bowser Jr.'s Journey mode of Mario & Luigi: Bowser's Inside Story + Bowser Jr.'s Journey.
The level has three battles. The first battle has four Swoops, two Bandits, one Goomba Tower, and a Goomba Tower first officer and captain. The second battle has the same exact formation, except that the first officer is a Bandit and the captain is a Swoop. The third battle has four Swoops, two Goomba Towers, one Bandit, and a Swoop first officer and captain.