Lego Harry Potter's gameplay is similar to that of most previous Lego games, with an emphasis on collecting and exploring. Casting spells is an integral part of the gameplay, with a wide range of spells available for unlocking as the player progresses. As there are many spells available in the game, you use the spell wheel to select your spell. Potion-making is another integral feature; potions can help the player complete levels or, if created incorrectly, have adverse side effects such as turning the player into a frog.
Changes to the mechanics of previous games include 'Student In Peril' missions, which are a group of challenges to help a student, Polyjuice Potion, which allows players to temporarily change one of your characters into any other mini-figure unlocked. A major change is to the hub system. On most versions, Diagon Alley works as a hub for unlockable extras, while Hogwarts acts as a constantly evolving massive hub with the unlockable characters found by picking up their hidden portraits.
The bigger areas in Hogwarts have led developer Traveller's Tales to improve the overall level design. If you are lost in-game you can follow a trail of Ghost Studs. These do not count towards your stud total, but will guide you to the next section of the level. 
Like the previous Lego games, there are a large number of playable characters. These include major characters like Harry Potter, Ron Weasley, Hermione Granger, Draco Malfoy, Albus Dumbledore, Rubeus Hagrid, Sirius Black, and Remus Lupin, as well as some more minor ones like Fang, Dobby, Buckbeak, and Centaurs. Most characters have a special ability, like Harry's use of his Invisibility Cloak, Hermione's ability to use books to solve puzzle locks, Scabbers and Crookshanks being able to move in tight spaces or Sirius' Animagus ability.
Characters will also have different strengths and weaknesses. For instance, Harry is a good broomstick rider and he is able to perform tricks and shoot jinxes when he is on a broom, Hermione is the best character at casting spells, and Ron can use Scabbers to crawl into otherwise unreachable areas.
1000 UNLIMITED FREE FULL VERSION PC GAMES PARTS SYSTEM REQUIREMENTS
Minimum System Requirements:
Operating System : Microsoft Windows XP/ Windows Vista/ Windows 7
Processor : Intel Pentium IV at 1.8 GHz / AMD Athlon XP 2200+
Video Card : 128 MB VRAM – NVIDIA GeForce FX 5800 / ATI Radeon HD 1300 Pro
Memory : 256 MB RAM (XP) / 512 MB RAM (Vista / Win 7)
Hard Disk : 4.5 GB of free Hard Drive space
Sound : DirectX 9.0c compatible sound card
Direct X : 9.0c
Controls : Keyboard & Mouse
Installation : DVD-ROM Drive
1000 UNLIMITED FREE FULL VERSION PC GAMES PARTS INSTRUCTIONS
1. Extract iso with winrar or 7-zip
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3. install the game
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1000 UNLIMITED FREE FULL VERSION PC GAMES PARTS