Drul Kantar is one of the two Oni warlords in Droaam. He's content to rule his little corner of Droaam, as the warlord of Thrakelorn and the surrounding region, and seems to lack the ambition of Tzaryan Rrac. He attends every gathering of the warlords that he can, and pushes his peers towards sustainability for Droaam and diplomatic relations with the other nations. He believes that coexistence is not only possible, but also the path forward for the monstrous denizens of his country, and seems to have bought into the dream laid out by the Daughters of Sora Kell wholeheartedly.
Drul Kantar's origins are unknown, he didn't leave Riedra alongside Tzaryan Rrac or Cavallah, neither of them knew him before he claimed the region surrounding Thrakelorn. It's possible he arrived in Khorvaire earlier than they did, like Szala Jal, or maybe he isn't from Riedra at all.