Griffin ignored the girl with telekinic abilities. He already knew what she could do. He watched the mug explode. He had no idea who had done that, but whoever it was was seriously dangerous. Then one of the girls cause the dust from the exploded mug catch fire. That was a useful skill to have. So far he had identified the abilities almost have the current prisoners. 
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Seeing the mug and the fire the guards reacted the way they had been trained. With a push of a button each cell was filled with a sleeping agent. This would knock the prisoners out for 10 to 15 minutes allowing the guards to remove all the dangerous materal. Natalie would lose everything not made of metal.