can you {snapcaster Mage} into a {ancestral vision}
No because it has no casting cost.
That's what I was curious about
This has no mana cost, which means it can't normally be cast as a spell. You could, however, cast it via some alternate means, like with {Fist of Suns} or {Mind's Desire}.
10/15/2006 This has no mana cost, which means it can't be cast with the Replicate ability of Djinn Illuminatus or by somehow giving it Flashback.