This guide shows where to find all the keys in the main menu.
Where to Find the Keys
Before anything, remember you need to find all the Nicknacks first.
As you can see in the picture above.
- Is shown without needed to do anything.
- This key is shown as well without needed to do anything.
- Is behind the shelf. Destroy the "painting" on the left which will reveal a lightbeam. That you will have to redirect with shield to unlock, and then drag out to reveal the key.
- Key is hidden inside shelf here as well (but below the 3rd). Drag out and then freeze to be able to remove the key.
- To get the last key you need to make the cabinet fall down to reveal a button.
I used the magic board from the wizard to poke the cabinet down.
Then use the fire arrow on the button behind the cabinet to reveal the last key, which will land on the chandelier.
Last picture will show where all the keys are shown once I've done the 3-5 steps.
Then simply use all the keys to unlock the secret main menu door.