Plate Keys Get itmes from the machine in the alchemy room by using the Plate keys. This machine only appears when you have beaten the game once.
Gives you Fairy Earrings: ALCHYMIA
Gives you Burst Shoes: POWDER
Gives you a Diamond Choker: ADAMAS
Gives you Alchemist Earrings: MORGAN
Unlock 'Hard' Mode and Secret Room: Beat the game once then go to the 'Main' menu and they will be selectable.
Alternate Dog: Complete the game once.
Alternate Enemy Costume: Play 'Hard' mode.
Stuffed Dog Costume for Hewie: Beat the game on 'Hard' mode
Unlock Cowboy Costume: Complete the game once with Ending 'A'.
'Illegal in some states' Costume: Complete the game once with Ending 'A' or 'B'.
Frog Costume: Beat the game with Ending 'C'.
Obtain the Obsidian Choker: At the first card slot in the game substitute 'METH' for 'EMETH' to view a different cut-scene and get a Obsidian Choker which you will find on the floor in front of the door.