The invaders who took Bordio realized the potential of a planet coverted to a Shield World. The very process begins with the very atmosphere being converted to a gas-producing shield, which ingeniuosly gives off gas and is powered by the same gas that is given off. These gases happen to be the noes essential to life on a planet. The only problem with such a shield is it crisscrosses the planet with artificial blue lines and the haze from the shield within these blue lines prevents stargazers from viewing out into the heavens above. The shield is very hard to break through and is the strongest shield the galaxy has ever witnessed. The shield is selectively permeable not unlike a cell membrane, allowing specific things through and other things not through. Unfortunately, if JST allowed the passing of weapons through one side of the shield, they were forced to pass it through the other side as well. The Bordio invaders got into the shield by converting ordinary trading ships into war cruisers and slipping through the shield. The shield pulse system only recognized ships by their shape and allowed them in.
The main disadvantages of a Shield World is that it fails to beautify a planet. The ugly haze produced by the shield discourages many people from even looking up at the sky. Most of the planet's land has to be converted to cities and large shield generators. This destroys forests and a large amount of diversity with it. Even lakes and oceans have to be covered with underwater shield generators and apartment complexes. The amount of light pollution given off by these bases destroys much of the undersea plant and animal life. Most of the inside of the planet is usually underground living areas, which are composed of ugly gray bombproofs. Many citizens live here because the size of the shield generators made them take up nearly a block apiece and this forced many from their homes. The underground fortresses are also used in times of crisis. Another disadvantage is the weaknesses that increase once an enemy is inside the shield. Because they draw energy from the planet's core, the shield generators can recharge the shield in a realtively short time but they are also very vulnerable where the energy meets to be projected onto the shield. If as so much as a missile hits this compressed energy, the shield generator will give off a collosall explosion with as much power and length as five atomic bombs, most often destroying the city they are in. Also, if one shield generator is destroyed, it is impossible for the shield to be reactivated unless the generator is rebuilt. And since the generators are interconnected to the planet's core, the destruction of one generator could start a chain reaction and destroy all the others, virtually ending all life on the planet.