His name means "Blade" in the Old Tongue. Mandarb is a highly trained warhorse, and like his master, is a living weapon. He is fiercely loyal to his master, allowing no one near himself without Lan's approval. So far, other than Lan, only Nynaeve has been able to approach and touch Mandarb with impunity. Mandarb remains in the general location of Lan at all times.
A notable accomplishment of Mandarb is when he threw himself into a ruined Waygate, forcibly opening it to let Moiraine Damodred, Lan, Loial and the young adults of the Two Rivers to escape the Ways while Machin Shin pursues them.
Mandarb is also notable for having, after a brutal attack from the Dreadlords led by Mazrim Taim in a precursor to The Last Battle, returned to the Borderlander camp against all odds. He sustained an injury on his left flank which leaves him permanently scarred, yet his reputation as a fierce warhorse and weapon is intensified as a result.