Instructions
Entering Umbridge's Courtroom
Open the gate and walk forward. You will see a cut scene showing a guard patrolling a hall.
Turn left and run past the guard. You will be invisible to the guards here unless you run into them or attack them.
Run out the door and turn left.
Head to the end of the hallway towards the gate and enter the door on your right side. Run down the short hallway and then turn left.
Watch the cut scene. Head right after the cut scene is over. Follow the wall, avoiding the wizards that appear, and enter the first opening you see.
Go down the hallway and hug the left wall to avoid bumping into the wizard guarding the way. If you are detected, use your Stupefy spell to defeat him and then immediately re-equip your invisibility cloak.
Turn left and walk down the hallway and out into the open area. Avoid the wizards and go right until you see a small bridge.
Cross the bridge and continue walking straight. Enter the large doorway on your right side. Stop before you enter the small chamber so that the wizard who is appearing does not spawn on top of you. After the wizard has spawned, walk around him and head down the hallway to your right.
Walk until you reach an area with pathways to your left and right. Take the left path and head down the stairs. Make the first right you see and walk down the hall past the two guards to enter Umbridge's courtoom.
Exiting Umbridge's Courtroom
Watch the cut scene. You can attack Umbridge with Stupefy spells as soon as you regain control of Harry.
Knock Umbridge down with Stupefy spells. When you knock Umbridge down, she will be gone momentarily, and few wizards replace her. Defeat the wizards using your Stupefy spell and then scan the room for Umbridge.
Watch the cut scene after you knock Umbridge down for the final time. Use your Patronus when the Dementors get close to you. Defeating all of the Dementors is the only way to open the exit of the courtroom.
Search the courtroom for the locket before you leave. Check the a stack of books near the front of the courtroom. Find the locket and then turn around and run out the open door to exit the courtroom.