When you enter Grimmauld Place ,after the Snatcher and Deat Eater encounter in the cafe,
you are told to go down to the kitchen (THE FAR SET OF STAIRS LEADING DOWN) you find a
vial of Doxycide and a bunch of pixies start to fight you. Use Impedimenta to kill them
not the Doxycide (TRUST ME, IT'S MUCH EASIER!!!!)
After the part where you kill the pixies in the kitchen you unlock Petrificus Totalus
(PETRIFICUS TOTALUS IS GOOD BUT IT IS A TEMPORARY SPELL MEANING IT WEARS OFF LIKE
CONFUNDO,EARNED IN THE NEXT MISSION,CONFRINGO AND EXPELLIARMUS ARE THE BEST SPELLS TO USE
ON PEOPLE,USE EXPULSO ON ACROMANTULA AND IMPEDIMENTA ON PIXIES.) You are then told to go
upstairs and explore. When you enter the room on the first floor, three pixies come at
you. Doxycide is helpful but you can waste it easily because the pixies keep moving. Use
Impedimenta blast to kill them and if you get low on health use Protego to hold htem back
and your health can then regenerate. Once you have killed two of the three pixies, two
more come at you. Use the same tactic to finish this part.
You then go back down to the kitchen after the cutscene to find Kreacher. After the second
cutscene you give Kreacher the fake Horcrux and he leaves to find Mundungus Fletcher.
After that part you go upstairs onto the ground floor and enter a room under the stairs.
The door slams shut behind you and you face a cupboard. A Dementor/Boggart comes out of
the wardrobe at the far side of the room when you go close to it and you now learn how to
cast Expecto Patronum (tap C then hold to release the spell. The faster the combination
and the longer you hold C will make the radius of the blast larger and it will destroy
more Dementors. Use this to destroy the Dementor.
Hermione then says to you to investigate a crashing sound coming from the kitchen, you go
downstairs and find Kreacher and Dobby clinging onto Mundungus. Shoot Stupefy continusly
at him to start up the cutscene about Umbridge taking the locket from him. This then leads
to Ron and Hermione leaving, and you to do 3 training missions. Once these are complete
you start a cutscene introducing the Ministry if Magic.