User blog comment:Zebrax8/Graviton Technology/@comment-169.139.176.84-20091117230903

Level 2 Graviton Tech would also be next to impossible to research also since the amount of energy that would be needed is ridiculous. The only reason to get Graviton Tech is for deathstars, yes. A great deal of planning is also required since you'll need a level 3 or 4 nanite factory.