Umakai trained under the powerful wu jen Setsu Iki.
In 1357 DR, after years of not seeing him, Setsu arrived in Ikizawa asking Umakai to take care of a page of the fabled Book of Hsi. Setsu explained that the evil Za-Jikku from the Quidemiplane wanted the book but it was safest being split in two, with a page in the far and isolated Ikizawa.
However, in 1358 DR, the yellow-robed minions of Za-Jikku twice attacked the village, greatly scaring Umakai and his villagers.
Later he met Osari Minhiro and a foreign adventuring party. After checking that they were good men, Umakai told them everything and gave them the page of the Book of Hsi.