Split Big Boo and trap all ten Boos
This mission is a Big Boo battle, not the final King Boo fight. Use Dark-Light to restore the missing train feature and begin the ambush. Dodge Big Boo’s passes and jumps until it misses and exposes its tongue. Grab the tongue with the Poltergust, aim toward the train’s front drill and release. The impact splits it into ten smaller Boos.
Reveal the scattered Boos with Dark-Light, pull each tongue and aim the Boo into an open train cage. The trapped Boos stay contained while the uncaught ones eventually merge again. Repeat the Big Boo stun, drill collision and individual cage shots until all ten are imprisoned. Take time to line up each cage instead of throwing at a closed side panel. Completing this mission records ten Boos toward the game’s total of thirty-two; there is no additional hidden eleventh Boo to search for here.
Collectible checklist
Boo checklist — Train model — ten Boos: Split Big Boo against the drill and shoot all ten smaller Boos into the train cages. Completing the battle supplies ten entries, not one.