Darkness surrounds you as you're sealed within the small, cramped confines of the Iron Lung submarine. The only source of light comes from the dim glow of the control panel and the blinking red dot on the proximity sensor. The silence is broken only by the steady hum of the engines and the occasional clanking of the hull as it contracts and expands with the pressure of the blood ocean outside. You know that your mission is important, but the thought of the unknown lurking outside makes your heart skip a beat.