The Restricted Section (1-4) - LEGO Harry Potter: Years 1-4
Year 1, Chapter 4
You'll start this stage with just Harry and Ron. You need to look out for the red books on the floor as these serve as sentries. Equip your cloak and approach them; press Y to kill them. After taking out the guard books, approach the ghost lady and wait for her to create a flower bed. Use WiLe to take out the cauldron. Now its time to look for the ingredients.
There are four candlesticks in this room so make sure you shoot them to make them sprout flowers. To get the popsicle ingredient, shoot the desk to the left then assemble the blue pieces with WiLe. Jump on the books to reach the ledge to the left. Use WiLe on the torch to melt the wall and grab the popsicle.
For the daisy and spider ingredients, you need to stand on the book held by a statue to the right. On the upper ledge, just grab the daisy from the planters there. As for the spider piece, shoot the peculiar looking shelf in the middle and wait for it to crash down, revealing the spider behind. Throw in the ingredients to blow up the door and to the next area.
In this section, you'll want to avoid getting caught by the old man. Do this by using the cloak to get past him. If ever he catches you, switch characters and shoot the cat to release Harry. This area is pretty simple; shoot the pile of books to the left to reveal a green piece. Go to the next book shelf and assemble the pieces so they'll find to the gate, according to their colors. Once the gate is opened, grab the green key at the end and use it to open the door. Don't forget to activate the two candlesticks here to get the Yellow crest piece. Go past the newly opened gate then shoot the books blocking the tube. Send Ron's pet to push the pile of books overhead. Use WiLe to place the missing door piece on the door to activate it.Exit there.
In the next room, shoot the spiders off the cobwebs to reveal a Green Crest piece. Those spiders drop a ton of studs so shoot them if you need them (or if you're just really greedy even with the multiplier cheat on)
Use LuSo on the vines to the left, then wait for the bats to perch before shooting them. Approach the mirror for more scenes and to complete this chapter.
Red Crest piece – if you haven't acquired this yet, use Hermione to solve the puzzle cabinet beside the large statue to the right.
Harry (Pyjamas) - Destroy the silver canvas holder near the bookshelves to the right.
Blue Crest piece – It is located behind the web where you got the spider ingredient. Use Crucio to destroy the obstructions and get the piece.
Again, there's nothing much to do here for now so follow the ghost guide's trail as it leads you to Hagrid's cottage and to the next story chapter.