How do you get Professor Quirrel on Lego Harry Potter?

You can't actually get Professor Quirrel as a separate minifigure in any of the Lego Harry Potter games. He is only represented as Voldemort possessing him, which you can encounter in various games, including:

* Lego Harry Potter: Years 1-4: He appears as the boss fight at the end of the first year.

* Lego Harry Potter: Years 5-7: He appears in flashbacks and during the final battle with Voldemort.

While there is no specific Quirrel minifigure, you can always use your creativity and modify existing minifigures to create your own version of Professor Quirrel!