Kamalashila
Kamalashila (Skt. Kamalaśīla; Wyl. padma'i ngang tshal) - This master was the main disciple of the great abbot Shantarakshita. He famously defeated a Chinese master of the Hashang school (whose personal name is sometimes given as Mahayana Hashang) in the great debate at Samyé, which took place around 846 AD, thereby ensuring that the Tibetans followed the Indian tradition of Madhyamika which had flourished at the great Nalanda monastery. His most famous compositions are the three texts entitled The Stages of Meditation, which HH the Dalai Lama has taught on several times.