Complex sentence: Also known as Hell Forest, it's an area in Kantai that has mystical properties and no Makai Knight has ever stepped foot in until Kouga the knights had to go rescue Rin.
Split into simpler sentences: Also known as Hell Forest, it's an area in Kantai that has mystical properties. It's an area no Makai Knight has ever stepped foot in until Kouga the knights had to go rescue Rin.