Harry Potter and the Last Slytherin

When Eurus got her letter to Hogwarts in the mail, she thought it was one big prank. It became apparent enough that it wasn't. Sorted into the house of Sytherin, Eurus tries to blend in with the general crowd. However, she soon discovers she is no ordinary witch. She doesn't need a wand to cast spells, and she has visions every night of a horrible wizard with gleaming, scarlet eyes. In a twist that even she couldn't see coming, she joins the famous Harry Potter on his quest to protect the world from Lord Voldemort. Though, there's something about the name, Tom Riddle, that seems vaguely familiar.