Angelica Engine

Angelica (also known as Angelica 3D) is a proprietary engine built in-house by Chinese developer Perfect World for its flagship MMORPG. The engine evolved into a whole family of internal versions — Angelica II powered Forsaken World, while an upgraded Angelica III was used for Swordsman Online, Saint Seiya Online, and World of Jade Dynasty. It's a good example of a game engine growing alongside a single company's titles over the years, rather than existing as a standalone commercial product.