Teancum Javelin is the weapon Teancum used against two Lamanite kings. Teancum “stole privily into the tent of the king, and put a javelin to his heart,” causing the king’s immediate death before he awakened his servants (Alma 51:34).
Teancum later entered the Lamanites’ camp by letting himself down over the city walls and going “from place to place” with a cord until he found the king. He “cast a javelin at him, which did pierce him near the heart,” and the king’s servants pursued and slew Teancum after the king awakened them (Alma 62:36).