Gamera: Rebirth - Code Thyrsos

Set 100,000 years before the events of Gamera: Rebirth, the comic depicts the downfall of the ancient kingdom of Elistania, which had begun manufacturing giant creatures known as Kaiju to stage artificial wars for the benefit of its elite. A boy named Lucius, whose father was killed in one such war, is disfigured in an encounter with a Kaiju and vows to see the aristocracy destroyed.

(Source: Wikizilla)