Activated all Commentary Nodes with the Developer Commentary Modifier enabled.
Open the secret bookshelf in the guest room from the outside.
Completed the game having found all 24 journal entries, with no Modifiers enabled, in less than 10 minutes. (From New Game in a single session only)
Completed the game in less than 1 minute with no Modifiers enabled. (From New Game in a single session only)
Completed the game having found all 23 of Sam's journal entries.
Completed the game.
Found Mitten's secret diary.
Turn on every faucet in the house at once.
Returned Christmas Duck to his rightful place.
Guess the combination to Oscar's safe before finding the code.