It was the Battle of Hogwarts. There were a lot of students and teachers who died, others fighting, many injured. Meanwhile Professor Severus Snape was slumped against the wall in the houseboat, dying. His throat was bleeding uncontrollably and Nagini's venom had already started to kill him. As you had a vision of Voldemort in the houseboat, you make your way to the scene and you can faintly hear the sound of a shallow breathing and mild gasps. The window is blood stained.