Klarg the bugbear was the leader of a group of goblins that were holed up in Cragmaw Hideout. He was filled with delusions of grandeur and viewed himself as a mighty warlord just beginning his career of conquest. He was not entirely sane, referring to himself in the third person ("Who dares defy Klarg?" or "Klarg will build a throne from your bones, puny ones!").
Marküs tried repeatedly to impersonate Klarg, with mixed success, until he finally introduced himself to a goblin as "Krag". Changing his story that "Krag" was Klarg's brother was not successful, as the goblin went to check with his leader, who promptly realized mischief was afoot, not having a brother. He attacked the party but was restrained by vines and slain.