Get an "A" in all ranks in the indicated chapter to unlock the corresponding figure.
Baby Spiders: Chapter 16
Barrel: Chapter 11
Behemoth: Chapter 9
Clown: Chapter 12
Corpse Kid: Chapter 21
Doctor Finklestein: Chapter 8
Fire and Ice Kings: Chapter 20
Green Elf: Chapter 22
Hanging Tree: Chapter 4
Igor: Chapter 6
Lock: Chapter 5
Mayor: Chapter 14
Mega Oogie: Chapter 24
Mr Hyde: Chapter 19
Oogie Boogie: Chapter 10
Pumpkin King: Chapter 5
Red Elf: Chapter 22
Roulette Oogie: Chapter 17
Sally: Chapter 18
Sandy Claws: Chapter 23
Santa Jack: Chapter 8
Shadow Oogie: Chapter 1
Shock: Chapter 7
Short Witch: Chapter 2
Super Spider: Chapter 16
Tall Witch: Chapter 2
The 3 Brats in a Tub: Chapter 15
Vampire #1: Chapter 13
Vampire #2: Chapter 13
Vampire #3: Chapter 13
Vampire #4: Chapter 13
Zero: Chapter 3
Defeat all monsters in the indicated location to unlock the corresponding figure.
Blue Skeleton: Hidden Place 6
Halloween Ghost: Hidden Place 8
Heat Skeleton: Hidden Place 1
King Ghost: Hidden Place 3
King Skeleton: Hidden Place 16
Orc Skeleton: Hidden Place 11
Trick and Treat: Hidden Place 17, after getting the Blue Ornament
Troll Skeleton: Hidden Place 5