1. Why not run 4 copies of SSG? You comment about how good it is, but only run 2 copies in one of the lists. ' REB of Will' is a very feasible answer to an early and fatal Flash.
There's no room. You don't want to drop under 17-18 land if you plan on running 5 or more colorless in the deck.
2. Why no Chalice? Chalice @ 0 is not only 'free' disruption on the play against MOST vintage decks(I'm not looking at you, Ichorid), but stops Summoner's Pact and Pact of Negation in addition to the moxen. It's also another artifact for Krark-Clan Shaman and has previously been in Vial builds of all kinds.
Chalice is terrible against most combo now. It's mediocre against Flash because it does nothing to them if they just have the combo or Brainstorm into it. Storm combo it's not that good without help. S'ok against Belcher I guess.
Pretty bad overall.
3. With no knowledge about the opponents deck (game 1), how can you know when to aggressively mulligan into a Leyline? This is an issue since Leyline is pretty much a dead draw unless you have Lotus.
you don't. why would you? Leyline is great, but hardly necessary in any given match.
4. You say the second list is "more experimental". Which seems to be the better list so far to take to a major(read: diverse) event from your experience? Take into account that it isn't like Flash takes up almost half of the field
Gonna say Vial build until I can work out the kinks in build #2.
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5. I like the idea of Vial-ing in a Stingscourger. Am I correct in assuming that this will work on Protean Hulk in response to Flash sending it to the graveyard?
Don't think it works. I'd check in the rules forum.