Ueda is the creator of two god-like swords, Ame-no-gozen and Tsuki-no-gozen. In fact, he is the father of his two sons. And he himself was one of the disciples of the god of time, one of the very powerful, but at the same time weak.

Ame-no-gozen was the sword of time and infinity and Tsuki-no-gozen was the sword of life force.

Ueda was in his temple of peace and time, apparently tired of all the fuss and he needed inspiration for his own strength.