DESC: This is exactly like having a 100% miss chance with the Insubstantial Power, but your entire body is affected at the same time, not just parts of it.

This makes you immune to all targeted physical attacks. You are still just as susceptible to area affect and mental spells. You can pass through cracks, doors and walls but at a max movement of 1 space per turn. While passing through a solid object you need not hold your breath as the "air" you breath is not a part of the physical world.

Since you are not a part of the physical world becoming solid is when you use your fatigue. Moving objects, making physical contact with a target is very taxing on you physically and mentally.