GRAVITY Co Ltd is an online and mobile games developer and publisher based in Korea. Its principal product, Ragnarok Online, is an online game which is available in more than 91 markets. Its games include Ragnarok Online, Requiem, Dragonica (Dragon Saga), Ragnarok Online II, Ragnarok Clicker, and Ragnarok Prequel II. The company generates revenue from online games, mobile games and other sources including character based merchandise and animation.