Quest for Elemental Mastery

Whenever you cast an instant or sorcery, put a
quest counter on Quest for Elemental Mastery.
Remove five quest counters from Quest for
Elemental Mastery and sacrifice it: Exile up to
two target instant and/or sorcery cards from your graveyard. You may cast those cards from exile
without paying their mana costs until end of turn.
A mental journey can be more arduous than a
physical one.