Just keep tapping the bottom right and if the opponent shoots at the top, all you do is block and it sends it straight back at him/her. Keep continuing this until you have won.
There are three bookcases in the Viaduct which have lots of Wizard Cards. Go out and back in to get loads.
When you get up to the mission which involves getting the presents for the Weasley's, go to the Hospital Wing to find a student that is willing to trade hers. The catch is though that you'll need a vial of induce of euphoria.
You can QUICKLY and easy dispatch ALL enemies by following this three step combo:
- Use Expelliarmus to knock them down
- Charge up your Stupefy, whilst getting that charged, walk RIGHT NEXT TO the person you're duelling against
- Fire your charged up Stupefy for a OHK
This has worked each and every time, and can give you 5 stars for the challenge VERY VERY QUICKLY & EASILY
You can get MASSIVE amounts of Mini-Crests, however you can only get it the one time only, and that's only when you have used the Luck Potion and are making your way to Herbology. At this point, every time you use Diffindo to get the Mini-Crests to appear, you'll get the full amount of Minicrests available (due to your luck). You should at this point get as much of it as possible, to make the 25,000 pieces that you need an easier target to reach.