Beterli is the oldest of most candidates and is not very handsome. He bullies Keevan and wants to grow up to be the best Dragonrider, however, he has always had no dragon choose him to become Dragonrider. He presumably feels like he is the only one who has been through the Impression many times, which provides motivation to make Keevan look bad, so he breaks Keevan's leg and cracks his skull in a fight. Beterli is known to set a fast pace to make people and others look at him as a big tough person, and make him appear better than everyone else. Throughout the story, he forces Keevan into thinking he is not going to be chosen at the Impression.
- Beterli Pern wiki