Castiel listened to them both carefully, nodding; this was all about what he expected, so that's good. He could practice a bit, try to gain some better control, and as a secondary goal he could try experimenting with just how much he could draw off in total before he ran out of energy or became too badly injured to continue. He wasn't going to bother mentioning that second goal.

"Alright. Are you both ready?" He was already beginning to lead the way to the emergency room, though, without waiting for a response. If not, one of them will stop him, and he was oddly impatient for a reason he's not sure of.