Indraugnir accompanied by Aenarion the Defender.
Indraugnir is the name of the Dragon that was ridden by Aenarion during the Great Catastrophe. He was with him during the greatest battles fought during those ancient wars. He died after bringing Aenarion and the Sword of Khaine back to the Altar of Khaine, with grievous wounds.
Sources
- Warhammer Armies: High Elves (7th Edition) pg. 16 - 18