Therin received the accolade of Weapon-Maker for his inventions of both bow and spear-thrower. As much a fighter as his older brother was not, he led some of the first serious clashes between elf and human after the founding of the Isle. He never had much skill in magic beyond a very modest ability for plant-shaping, though he strove to improve his skills out of a sense of duty, if not desire. Nevertheless, his Recognition with Maka resulted in the Isle's first Healer, Dlen.

When he lost his lifemate Maka, he lost with her much of his sense of humor. Sharp-tempered, increasingly impatient with less-skilled hunters and warriors, many in the Isle fervently hoped that his Recognition to young Sharpgrass might soften his personality. But those hopes were dashed when Sharpgrass and her daughter were the first victims of a surprise attack while the elves were celebrating the completion of the LakeHolder.