Instructions
Choose to play a mission in "Dark" mode via the screen that provides this option before beginning a level. "Hero" and "Neutral" modes are also available, and when a mission allows only the "Neutral" option, this indicates that you can use both Chaos Control and Chaos Blast during that mission.
Kill non-player characters who fight on the "Hero" side of the battle, such as Gun Soldiers. This fills the red Chaos Blast Gauge on your screen. When it fills fully, Shadow begins to glow red, and will continue to glow as the gauge diminishes, until both deplete.
Press "Y" to unleash the Chaos Blast, an explosion that fills the screen and decimates opponents as well as destructible items in the environment. It can be used four times with a full Chaos Blast Gauge.