Mario & Luigi: Bowser's Inside Story (DS) - Bowser’s Castle - Shroobs

Return to Bowser’s Castle and you’ll find a trio of Shroobs at the preservation area. After entering a password and pressing a red switch to thaw the Shroobs out, they will challenge you to a battle. The Shroobs will use guns to shoot oval lasers and spin around the brothers. After you defeat them, you’ll receive 10 Attack Pieces and learn the special attack Magic Window.