All card decks
To get all the card decks from the beginning of the game, defeat Voldemort four times.
All spells
After successfully completing the game, use the card combination that Dumbledore gave you at the end of the game at the first battle you encounter. It will give you all spells and allow you to keep them for every future battle.
Aconite
If you are having trouble finding Aconite for Herbology, go into a grassy area below Hagrid's Hut. Press [A] where there are the little flowers to get Aconite.
Famous Witches And Wizards Cards
There are some Famous Witches And Wizards Cards in the Forbidden Forest when you are on your detention. To get them, go up to the trees and press [A].
Full Incendio spell
In a battle, select "Spell", then "Incendio Tria". Then, press [Left]. The spell will now be targeting all of the creatures. Note: This spell does less damage than if done on one enemy.
Mucus Ad Naseum curse
Instead of finding the Mucus Ad Naseum curse in the restricted section, there is another way to do it. Before you go into your Defense Against the Dark Arts class, make sure your MP is 80 or above. Peeves will then put a curse on you, Mucus Ad Naseum. Tell Professor Quirrel, and in the Muggle Studies classroom you will find a television. "Walk" through it and it should lead to another room. Fight the monster at the bookcase and when he is defeated, you should receive a book. Go to your items, cure yourself by using it, and (if your MP is 80 or above) you will learn Mucus Ad Naseum. Return the book to Madam Pince afterwards. Mucus Ad Naseum is a very helpful curse when battling Voldemort, Professor Quirrel, and other Bosses, such as the troll in the bathroom.
Petrificus Totalus and Potion recipes
When you can enter the restricted section, go to the top left book case. Search to the left of the book case. It costs 60 MP, but they cannot move until you attack them with a different spell. If you have the Mucus Ad Nauseam spell, and if you use it before Petrificus, it will not normalize them. You can also get potion recipes and spells such as Locomotor Wibbly (10 MP, same as Petrificus only it does it for one turn). Additionally, Petrificus works on all enemies (even Voldemort).
More herbs
Stand in front of a piece of grass where you get herb plants. Pick it up, go into your menu, and exit out. More herbs will appear there.
Use the "More herbs" trick and you can get more than 9 herbs. Though your Ingredient Encyclopedia says you have 9, you may have 99. To find out how many you really have, press [Start] then select "Items". Go down and find the Ingredient. It will show you the number you actually have on the right side of the screen.
Quick items from bushes
You can get items at the strange bushes very quickly. Press [A] then enter the start menu. Exit the menu and press [A] again and another item will appear.
Snape's potion ingredients
When you have to look for ingredients for Snape, if you do not go directly in his office and search the poster and search for the other potions beforehand, the game thinks you already have it and the Boomslang Skin will not be there. To get around this, go outside after finding the other two potions. If you cannot find the Boomslang Skin, go outside and search everywhere for it. You can find it in strange looking bushes, trees, grass, etc.
The Boomslang Skin is usually on the Boomslang picture in Snape's office.
For the Beetles Eyes, talk to Hagrid. He says something similar to "I've got to get me some rest since I've been spraying beetles". Go to a small bush to your left to find the first portion of Beetles Eyes. The second is on the sixth floor of Hogwarts, in the mini secret room filled with hieroglyphics. Enter the room, find it, then go back outside.
For the Snake Fangs, talk to Professor Sprout. Walk into a magical encounter, look for a snake, and fight it. Once you get at least one set of snake fangs, go to Professor Sprout and she will award you 1 House Point. You may still fight the creatures to get more House Points.
Once you are done getting the ingredients, go to Professor Snape and he will award you 5 House Points. Then, complete the rest of your lessons.
When you find a ingredient plant, get the ingredient and press [Start]. Leave the menu then get the ingredient again. You can do this as many times as desired, but you can only carry nine ingredients of each type.
Incendio
To get Incendio, go to Professor McGonagall's class on the first floor and catch the rabbit to learn it.
Wiggenweld Potion
In Gringotts' Lobby, you can get a Wiggenweld Potion by going to the space at the left in the middle. Also, the top right seat which is empty has a Famous Witches and Wizards Card.
To get more Wiggenweld Potions, when you are getting rid of your Curse of the Bogies, go see Madam Pomfrey. She will give you a Wiggenweld Potion to take. If you do not need it, try to save it for later. Another method is go in the doors to the right of and behind Madam Pomfrey. Select some objects and you will find potions in both rooms.
Easy spell levels
To get higher spells faster, for example from a Verdimillious Uno to a Verdimillious Duo, keep using Verdimillious Uno. You will soon have Verdimillious Duo. Also, to get the Tria of a set of spells, use the Duo.
Cheaper spell
If you have the card combination "Scholarship" completed, cast it during a Boss battle to have all your spells costing half of the MPs (magic points) normally required. For example, Flippendo Duo normally costs 4 MP, but after casting Scholarship, it costs 2MP.
Hidden spell
In the restricted section in the library, there are three vertical bookcases. The first one has a spell called Mucus Ad Naseum, which is useful when defeating the Devil's Snare towards the end of the game.
Easy house points
Before going to Hagrid's hut (when Harry found out about Norbert), go to the place where you have Flying lessons after getting all the card combinations from the Card Collectors Club. Then, talk to Madam Hooch and she will tell you to chase an owl. After catching it, you will be given 10 house points and a card combination. This can be done repeatedly, as long as the card combination are collected first.
Lose all of your House Points
When you get to the part where you need to find the trophy room to duel Malphoy, go to the fourth floor. Note: Sometimes she is on the third, fourth, or fifth floor randomly. There will be an old lady standing watch. Talk to her twice. The second time she takes away one House Point. She keeps taking away one House Point every time you talk to her.
Easy level up
Go to the hospital wing. If you are injured, talk to Madam Pomfrey. She will heal you completely. Then, go to one of the rooms beside or above Madam Pomfrey. Fight as many people as desired. When you get hurt badly, return to Madam Pomfrey to get healed. Repeat this as many times as desired.
Easy money
Go to the Quidditch Pitch on the far right. ,Go down to the bottom of the pitch until you see a plant that looks like a large monkshood (just beside the gate on bottom of the pitch). Search it for a Unicorn's Horn. Pause game play and get another one. Repeat this until you have a large number of them, then go to the Weasly Twins and sell em for 38 each.
Class levels
Hagrid's Hut: Outside
Herbology: Outside
Flying Class: Outside
Potions Class: Entrance Hall on left side of staircase
Transfiguration Class: First floor on upper left door
Charms Class: Second floor in the big brown door
Defense Against the Dark Arts Class: Third floor on the upper
left hand door
History Of Magic Class: Fourth floor on upper left door
Astronomy Class: Seventh floor
Bonus games
The bonus games are Chase Draco, Catch Norbert, Get The Golden Key, Copy Flitwick, Potion Mixing, and Cards Match games.
Find your Christmas presents
On the sixth floor, go to Filch's office. Go to one of the chests and press [A]. Your presents will be there, but no matter what, you will lose 1 house point.
Exploring Hogwarts with the Invisibility Cloak
After you find your presents for Christmas, that night you will have to explore Hogwarts. First, go into the library, and look in the bookcases in the Restricted Section. While in the Restricted Section, people will know that there is someone out of bed. Go up one of the staircases found in the library. You can walk by Madam Pince or go to the other side and get out of the library that way. Then continue up all the stairs until Mrs. Norris is found in the middle of the only stairs going up. This should be on the fifth floor. Do not go up the stairs -- Filch will catch you. Instead, go to a hallway that normally has a locked door at the end. Once you enter the hallway Snape and Filch talk for a second, then continue down the hall and into the room, to the Mirror of Erised. Dumbldore will be there, and will send you back up to Gryffindor. No house points will be deducted.
Cauldrons
While at Diagon Alley and buying school supplies, you may consider buying both cauldrons in the Cauldron Shop. More potions can be made when you have both of them. If you only have enough money for one, the collapsible cauldron is used for Wiggenweld Potions. It is a good one to have.
Potions
To get more potions recipes, look in the library. Every once in a while on a bookcase, you will find a recipe, a spell, or other little items.
Bonus games
During Charms, do not stop when your feather is at the top. You will have to start all over again until you have won the entire game, not just one level. For the games when you use your broomstick, keep pressing [Right]. It makes you go faster, even if it makes you bump into objects at times. One exception is when catching the golden key. Do not try to avoid other keys; just keep pressing [Up] and when you get to the top, you may have to move around a bit. However, you will get there if you keep pressing [Up].
Getting Norbert away
When it is the night to give Norbert to Charlie's friends, go to Hagrid's Hut, then go back up to the seventh floor. Go past the mini-hallway to the picture of the Pink Lady and go into the next door on the left,. Go through all the corridors, and go up to the top of the tower. You cannot do anything about forgetting the invisibility cloak. Once Norbert is gone, just leave. There is nothing you can do about losing house points.
Duel with Draco Malphoy
When you have entered the trophy room, go straight to your left. Keep going until you find a big door. Once there, Filch will have entered the room and Mrs. Norris will be looking for you. Go through the door and you will be in another room. Then, search for another exit. You will have avoided Filch with losing any house points.
Get rid of unwanted monsters
If you feel that you are not strong enough or just do not want to battle the monsters in the game, an easy way to make them go away is to press [Start] for the menu. Quickly exit and the monsters will not be there. They will unfortunately return, but simply repeat the trick. This is best used when you are in the beginning at Gringgots or in the Hogwarts Dungeons. This trick is especially useful at the end, when you must go to the Forbidden Corridor.
Get rid of your curse
Go to the Muggle Studies classroom, on the fourth floor corridor on the left side. In the top-right corner there is a "TV" thing. Press [A] in front of it and it will lead you to a secret room. Fight the monster inside. After you defeat him, you will get a curse book. Find it in your items list and select it. It will automatically heal you. Afterwards, you have to take the book to the library.
Get the Gryfendor password
When Nearly Headless Nick asks you for an old school tie, go to the entrance hall, then go to the second gargoyle and press [A]. You should see a tie in your item list. Then, return the tie to Nearly Headless Nick and you will get the password to Gryfendor.
Catching the purple rabbit
To catch the purple rabbit that Professor McGonagal sent you to do, go outside of Hogwarts. Walk to the left and right next to the first greenhouse. You will see the purple rabbit. In order to catch it, you first have to fight it.
As soon as you are sent out to get the purple rabbit, do not waste your time doing other things. Go directly to Herbology and to the right of the farthest greenhouse to the right, select the rabbit. If you get there fast enough, you may not have to fight it.
Defeating Forbidden Corridor monsters
Devils Snare: Incendio Duo
Knight: Incendio Duo
Rook: Incendio Duo
Bishop: Flipendo Tria
Professor Quirrel: Incendio Duo
Voldemort: Flipendo Tria
Alternately, cast Locomotor Wibbly/Mortis, cast Mucus Ad Nausem, then Keep hitting flee until the Boss is dead. Note: If the Boss returns to life, cast Locomotor Wibbly/Mortis again.
Alternately, cast the following:
Devils Snare: Incendio Tria
Chess Piece 1: Vermillious Tria
Chess Piece 2: Verdimillious Tria
Chess Piece 3: Flipendo Tria
Professor Quirrel: Vermillious Tria
Voldemort: Mucus Ad Nauseum and Petrificus Totalus
Defeating Bosses
Rats: Vermillious Duo (big); any spell (little)
Suit of Armor: Flipendo Duo
Rock Man Thing: Verdimillious Uno/Duo/Tria
White Rat: Flipendo Tria, The Incindios; little purple ones: Incindio
Duo.
Devil Snare: Incindio Tria (big); any Incindio (little)
Chess Pieces: Mucus Ad Nauseam, Flipendo Uno
Prof. Quirrel: Incendio Duo or Tria
Voldemort: Mucus Ad Nauseam, Petrificus Totalus, Flipendo Tria
Defeating the troll
Train to level 21 in the empty classroom and McGonnagol's office. Keep training until you get two Pepper-Up potions, then kill yourself. Ron will give you full SP and MP. Fight the troll using Virdimmilius Tria and when you get less than 16MP, use a Pepper-Up potion. Keep using Virdimmilius Tria and the troll will die.
Defeating Voldemort
After defeating Quirrell, Voldemort attacks you. Use Mucus Ad Nauseam, then Petrificus Totalus, then select "Flee" until he returns to normal. Then, use Petrificus Totalus again and keep selecting "Flee". When he only has a small portion of SP remaining, he will turn to normal. Then, keep selecting "Flee" until Mucus Ad Nauseam kills him.
Train to at least level 65. Go through the forbidden corridor. You will see Quirrel there. You will have to fight Quirrel. After that, Voldemort attacks you. First, use Petrificus Totalus to paralyze Voldemort. Then, use these card combinations: Protect, Deflect, Strength, Improved Magic. When you are using these combinations, if Voldemort becomes unparalyzed, hit him with Petrificus Totalus. Then, use Mucus Ad Nauseum. Voldemort should then come back to life. He will attack, but not do nearly as much damage as normal. Then, use Flipendo Tria. This should do at least 100 damage. He will soon be defeated.
Levels, Cards, Sickles and items
First, you need to have about 2,000 thousand Sickles. Go to the Wizard Card Trading Club. Buy at least 500 Chocolate Frogs and open them up. A lot of your cards should have "9" as the quantity. Make sure you have lots of Card Combinations that have checks by them. Battle something, preferably three monsters and one that gives a lot of experience. Save your game (before each attempt as well) and then restart. Go to the item selection screen and choose "Folio Tripculus." Now, choose a Card Combination that has a check by it. You should now be on the battlefield as if you just won a battle. Your experience and amount of Sickles that you got from the battle should now be doubled. If you want to do this again, save before and after each attempt -- the game will sometimes freeze while the spoils for the battle screen appears. Repeat the process if this happens. Also note that if you received an item in the battle, you will receive one more of it if you do the trick, Remember, the more experience you gain, the more faster your levels will grow. Also, when you reach levels in the 80s, you will gain all the abilities:
Filpendo Uno, Duo, and Tria
Vermillious Uno, Duo, and Tria
Verdmillious Uno, Duo, and Tria
Incendio Uno, Duo, and Tria
Locomoto Wibbly, and Mortis
Wingardium Leviosa
Petrificus Totalus
Mucus Ad Nauseam
Easy Sickles
When you are on your way to Snape's Classes, or at any other time, look for a silver box on one of the floors. Go up to it and press [A] to automatically get 117 sickles.
See Harry's parents
Go to the floor where the Gryffendor common room is located. Find the big orb floating in the middle of the room. Stand "in" it, and you should see Harry's parents instead of Harry.
Forbidden Forest warning
After you finish your detention and you decide to walk around before going to bed like you are supposed to, do not go back into the forest. You will not be able to get out.
Forbidden Forest
When in the Forbidden Forest, go to the fourth section to find Hagrid and the sixth section to find the unicorn.
Glitch: Phantom conversation
When going to Snape's Potions Class, note that the Weasley Twins are still in the Common Room. Press [Start] and walk to where they where standing. Press [A] and you will be talking to them, even though they are not there.
Glitch: Neville teleports
When Neville's broom takes off in flying lessons and he breaks his wrist, Madam Hooch will walk to where Neville was standing before his broom had taken off. Instantly, Neville will teleport to that location.