Harry, Ron and Hermione have each the following special ability:
Harry - Jump long gaps
Ron - Finds hidden passages
Hermione - Crawls under small spaces

Once you have completed all the tasks and have opened the chamber on the Neville and Goul level light Lumos Duo in the Gouls eyes and then lead it into the chamber to lock it in.

On the same level as the Goul you will meet Hinkypunks which are ghost-like creatures who have one foot and a lantern.

Have Ron shine Lumos Duo in their faces and when they become solid and zombie-like shoot Flipendo at them to defeat them.

Return all of the lost objects from the notice board in the Gryffindor common room untill you find the key.

In order to unlock the locked door on the sixth floor and the locked chest in the Muggle Studies area.

The key is located behind the statue on the first floor.

When you come across a moving bush when you are exploring the grounds of Hogwarts move up close to it and shoot Flipendo at it.

A jelly bean, Wiggenweld or Antidote potion will pop out of it for you to pick up.

Use a Glacius spell on a Salamander to put out the fire on it's back and turn it to ice then hit it with a Flipendo (Knockback Jinx).

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