War Mage Artius:
Actually, there is a Temple of Shilen beneath Keucereus Alliance Base. It is so secret that nobody knows about it. There is a priest of Shilen in hiding there. His name is Lelrikia. I think we need to ask him about this.
The entrace is guarded by Soldier Ginby. He seems to be in the pay of the priest these days, so his loyalty is suspect. But go to him and ask him to let you in.