King Nachtigal was (at first) the secondary antagonist in the 2011 video game Tales of Xillia. He, along with Gilland, planned to have the Lance of Kresnik for their own purposes. He was the one to have built it in the first place, though Gilland talked him into doing it. It was also revealed that Nachtigal was friends with Rowen Illbert years ago.
In Tales of Xillia
Nachtigal had citizens from Sharilton in a lab inside a gorge against their will. He had Gilland and a few soldiers kidnap Milla, Drisselle, Elize, and a few more citizens into Fort Galanda. Later on, Milla pursued him, but her legs got destroyed after he and Gilland got away.
In the palace of Fennmont, Nachtigal fought against Jude and the group. After the fight, just as he was convinced by Rowen that what he was doing was absurd, Nachtigal ended up being assassinated by Gilland's spirit "Celsius".