Lak 'Vadamee was a member of the Vadam family, rulers of the powerful State of Vadam. He was old for a Sangheili and was an Elder of the Vadam lineage. He served as an adviser to Thel 'Vadam and was the one who taught Thel how to fight and use his reasoning skills from such a young age. He is known to have a relation to the Arbiter Thel 'Vadamee as they both have the same pre-fix of their name. Lak is known to have served in the Sangheili Military Forces as his name has the 'ee' suffix.