Mission 27: Investigate Beast's Castle
 Mission assignment
Team up with Xion and gather intel in Beast's Castle.
 Story summary
Roxas and Xion travel through the Beast's Castle, taking closer looks at their surroundings.
 Mission walkthrough
You start on the upper level of the Entrance Hall, as this is a reconnaissance mission, your job will be to spot clues as you roam around. Two optional recon points can be found on the Upper Level: one at the northern most part of the area, in the form of a stained glass window, and one in the form of a crate along the straight southern hallway. Once you check these out, head for the Courtyard. A pile of bread crumbs in the southeast corner serves as an important recon point, but you can also examine the statue in the northwest corner and the footprints near the statue in the northeast corner. Be sure not the miss the Bulky Vendor on the southern end of the courtyard, either. Enter the castle through the main doors after grabbing the chests in this area.
In the castle, there are two more points to examine. The important point is a set of claw marks to the west of the main door, and the other, optional point is the northeastern door on the main floor. After taking out the Heartless here and snagging the treasures, proceed to the West Hall. After a short cutscene, you will achieve your first breakthrough.
Lumiere will be guarding the lower hallway, and you will have to sneak past him. He moves quickly, but he goes back and forth around the middle of the hall, near the bottom of the stairs. Watch his pattern closely, and he should be easy to sneak past. There is also an optional item to examine here: a mop in the southern alcove next to the stairs. Don't forget any treasure chests as you tiptoe around Lumiere to enter the West Wing.
As soon as you enter the West Wing, you will be accosted by a new type of Heartless, the Snapper Dog. Defeat it and its two Bad Dog companions to proceed. There are three more spots to examine: claw marks on the lower wall near the treasure chest, footprints at the top of the stairs, and the door at the end of the hall. After checking the footprints and the door, you will have two questions to answer, and you will achieve your second breakthrough.
At this point you will have reached the end of the main mission. However, achieving a full Mission Gauge will be along your way out. Head back to the Entrance Hall. When you get there, listen at each of the four doors on the main floor. Answer Xion's question, and voila, the extra goal is reached, and you can now RTC.