[quote="susan_brindle"]
Wizards can also harvest the stored energy, and dragon eggs are the most "common" ritual component, to the degree that anything involved in epic level magic can be called common. Most wizards do not have a dragon's egg, but amongst the handful of 14th level wizards, maybe half of them do, with about half of those having two or more.
[/quote]
That there is a damn neat twist on the whole "Philosopher's Stone" sort of theme.