Capturing is all well and good, but do consider the sheer size of the frost wrym in question. Should she struggle and come crashing down, she will do considerable damage. Her sheer size also means turning her to aim for a less... destructive landing could be difficult.
That said, I'm well versed in crafting, enchantment and frost wryms.
un: Black Prince; text
That said, I'm well versed in crafting, enchantment and frost wryms.