Complete the game to 100%

Turn the sound down to 0 and music off in the options menu whilst in the library

Defeat Quirrell in the Quirrell boss fight, using Voldemort

Defeat 20 enemies with Fang

Defeat 10 enemies with a Muggle character

Scare 20 students using a ghost character

Buy the entire Gryffindor Quidditch team from Book One

Collect all of the Red Bricks

Rescue all students in peril

Unlock all Animagi

Use the Time-Turner

Get True Wizard in every level