The docility was an encouraging sign, though Erik wasn't prepared to let his guard down. He nodded in acknowledgement of Pietro's thanks and sat back against the wall to smoke, looking around thoughtfully. "Bit dreary in here," he remarked eventually, deadpan, and then raised his eyebrows as he regarded his son. "The cells are nearly empty, you're one of the last down here," Erik said conversationally and took a long drag of his cigarette. "I could let you out," he mused, as though the thought had only just occurred to him. It was a calculated but risky move, given that there was no more mutant suppressant serum or working collars. Magneto had made a big show of destroying some of the collars, "the shackles of humanity" he'd called them, but in reality they'd simply run out of power. It was the same with the stores of serum running dry. Resources were precious and not worth wasting on devices to control a populace that was essentially trapped by their circumstances; living on an asteroid speeding through space. Magneto thought that perhaps his lack of means for direct control might actually work in his favor if it made Pietro feel less like a prisoner.