Thor

"She won't go through life bald," said Thor. "Because, Loki Laufey's son, if you do not put her hair back right now, I am going to break every single bone in your body. Each and every one of them. And if her hair does not grow properly, I will come back and break every bone in your body again. And again. If I do it every day, I'll soon get really good at it," he carried on, sounding slightly more cheerful.
"No!" said Loki. "I can't put her hair back. It doesn't work like that."
"Today," mused Thor, "it will probably take me about an hour to break every bone in your body. But I bet that with practice I could get it down to about fifteen minutes. It will be interesting to find out." He started to break the first bone.

[...]

Loki clambered to his feet and hurried away before Thor could break any more bones.