Lex was observing the facility, considering how he could enter without attracting attention. The surrounding area was pitch dark, but the facility was still well lit. They probably had spirit energy powered lanterns or something similar. But instead of helping them, the light acted as a beacon for the robotic invaders, attracting their attention and resulting in this siege.
Their defensive formation was like a transparent bubble around the entire building, only rippling when struck by the invaders - so that meant it was constantly rippling. He didn't know how much longer the formation could last.
Before Lex could formulate a plan on how to proceed, Mary called out to him.
"Hey Lex, before you do anything else, I just learned something I thought I should share with you."
"What's up?" he asked without removing his gaze from the facility.