Syltherin

Slytherin and Gryffindorshare an enormous rivalry, and thus are extremely competitive with one another. A Slytherin are usually the "pureblood", and great wizards though the wizards and witches in that house usually end up evil. The first headmaster of this group was Salazar Slytherin, he created it as Godric Gryffindor started Gryffindor house, Hufflepuff to Helga Hufflepuff, and Rowena Ravenclaw to Ravenclaw.

However, this may be taken with a grain of salt, as Gryffindors and Slytherins have shared a fierce house rivalry since their founders, Godric Gryffindor and Salazar Slytherin, respectively, had a severe falling out over Slytherin's emphasis on blood purity. There might also be an element of jealousy;as Harry and his fellow Gryffindors tend to win in a lot of circumstances which, when viewed from a Slytherin's point of view, may be considered unfair. Examples of this include the last-minute points awarded by Headmaster Dumbledore at the Leaving Feast, which conveniently put Gryffindor ten points ahead of Slytherin in the 1991–1992 school year, and Harry being permitted by Professor McGonagallto have his own broomstick for the Gryffindor Quidditch team, even though first-years are not normally permitted their own broomstick.

Overall, however, the houses of Ravenclaw and Hufflepuff tended to side with Gryffindor in its rivalry with Slytherin. This was particularly notable during the Second Wizarding War — the members of Dumbledore's Army were from Gryffindor, Hufflepuff, and Ravenclaw, but lacked any Slytherins, and during the Battle of Hogwarts, the Slytherin students left while many students from the other three houses remained behind to fight against Lord Voldemort.

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