This is for special training sessions with Ketsu. The ground is black from decay, and the air is full of the battles taken place here, the smell of fear is overwhelming. The ground has large spikes out of the ground, and a pool of blood that can power Ketsu's zanpakutou to an extreme degree. A fight here is death for anyone besides Ketsu, and is a hidden place that he trains for strong attacks, and for his own personal power. He is said to train at his full power here.