Along with the regular PS3 trophy’s and Xbox 360 Achievements there are also 8 additional secret trophies and achievements:

20 Xbox Achievement Points or Bronze PS3 Tropies

We Have the Talent! – Finish the Firehouse training stage.
The Flowers are Still Standing! – Finish the “Welcome to the Hotel Sedgewick” stage.
Once S’more into the Breach – Finish the “Panic in Times Square” stage.
Get Her! – Finish the “Checking Out the Library” stage.
Ghost Fever Grips New York – Finish the “Museum of (Super)Natural History” stage.
Somebody Saw a Cockroach on 12 – Finish the “Return to the Sedgewick” stage.
Let Me Guess, Gozer Worshippers – Finish the “Lost Island Rising” stage.
Disaster of Biblical Proportions – Finish the “Central Park Cemetery” stage.

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