Harry Potter and the Deathly Hallows Part 1

ok woah the book was awesome i finished over the weekend there are so many things i want to know and one is a really big one is what made ahrry come bakc to life cuz i dont get that so and to the others that wrote things before the book came out they did a really good job on guessing like the person who a dit the scar was a horicinx cuz they were right so i also want to know who is victiore she is in the epigoue snogging teddy lupin so and the cousin of someone so oh and who killed the snake cuz harry told neville to do it if something bad happened and when voldy put the boddy nears his feet...