There are many places to watch the complete third season of the Vampire Rider online. Some of the common online viewing platforms include: 1. QQ Video: The complete video of the third season of Vampire Knight can be watched by paying or free. 2 iQiyi: iQiyi also has a video of the third season of Vampire Knight that can be watched by paying or free. 3 Youku: Youku also has the video of the third season of Vampire Knight that can be watched by paying or free. 4. Sohu Video: The third season of the Vampire Knight is also available on Sohu Video for free or paid viewing. It should be noted that when watching the complete third season of the Vampire Knight online, you need to choose a platform that suits your network status and payment habits, and ensure that the video resources on the platform are legal and reliable.