Quest for the Aetherium Forge

Whenever you cast a noncreature spell, put a
quest counter on Quest for the Aetherium Forge.
Remove four quest counters from Quest for the
Aetherium Forge and sacrifice it: Search your
library for an artifact card with converted mana
cost 6 or less and put it onto the battlefield.
Then shuffle your library.
"Perhaps the Forge, like the secrets of Aetherium itself,
remains to be discovered..." ~ The Aetherium Wars