@Stormanimagus no I’m saying you put this in your deck because you win 40% of games by casting one or more free super preordains into an always on thassa turn 1 and the other 60% of games you play out with 4 copies of the thassa in you deck, because your deck probably can manipulate copies it doesn’t need to the bottom, shuffle them away, or otherwise make them magically turn into other cards.
A player is on the draw on average 50% of the time. Truth be told I think it can be higher than that if you so choose since most other decks and players would opt to go first but if you win the coin flip you can still opt to be on the draw. I don't think you can opt to have it go the other way for the most part, and obviously this only holds up as long as the meta dictates playing is the optimal choice for other people.
So even if this card had a negative 10% winrate on the times where you start on the play, but a 40% increase on the times you are on the draw, net net you would run that card because your overall winrate would still go up.
I think this is really interesting analysis that we do not see very often to be honest, because most people gear all their analysis assuming you opt to be on the play whenever possible. What if a lists optimal scenario actually was to be on the draw. I would even go as far as to say I suspect a list like Oath might even be better off on the draw in most match ups, as it is not looking for tempo but combo pieces and control and ideally an opponent who slams down a creature turn one to make it so all they need is oath and a mox and can forgo needing forbidden, though I do not think I have seen that analysis on these boards.
You guys are focusing on the wrong stuff. First, whoever said Sphinx is a free Preordain is wrong: it's a free Ponder (you see 4 cards down if you want). Second, it is a great tempo advantage. Let me give you an example:
Take this hand, in Xerox (and I'm not even saying Xerox should play this, since the 4cmc is kinda too high, but anyway). You're on the play:
Force of Will
There's a built in tension with this hand. Do you Preordain turn 1 to find land to make this hand playable, or do you hold Pierce up to have double counter against an unknown opponent? (I put in Pierce instead of Fluster to make this more relevant against Shops, but whatever). It's a hard call, and I'd say most of the times you'll have to Preordain or else you run the risk of having to Preordain turn 2 with that same 1 land, not find land and be open to a 2nd turn play, which is more dangerous.
If you have to FoW, you'll probably lose either one Preordain or Cruise, which is not anything that backbreaking, but if you didn't find land with your first Preordain, you'll want that second, and Cruise is a game winning late card.
Now take the exact same hand but -1 Preordain +1 Sphinx of Foresight, also on the play:
Sphinx of Foresight
Force of Will
This hand is amazing. You will "Ponder" turn 1, which is very likely to get you a land for turn 2 (it "sees" one more card than Preordain) but, more importantly, you can do that while also leaving mana up for Spell Pierce. You don't even need to fire up your Preordain that soon, since you can milk that advantage Sphinx gave you, and you only need to break the fetch if your opponent really does something that'd would win him the game. And truth be told, if you did something like bottom all 3, breaking the fetch is not even that much of a loss - it is, but not as much as if you top all 3 and plan your next 3 turns with it. Anyway, you'll have full information to choose what to do. Also, you'll not have to lose your Cruise or 2nd Preordain for your FoW.
Can you even imagine that scenario with 2 Sphinx in the place of 2 Preordains? You'll see 3-7 cards down. That kind of fureproof planning is amazing, and you're 100% guaranteeing that Pyromancer turn 2.
@evouga The CA on both is +0. So yes it's just like Ponder. You end up with the same number of cards in your hand. You can discuss the quality of those cards, but it's an effect much more equivalent to Ponder than Preordain.
The second Sphinx is diminishing returns, for sure, and worse than the second Ponder, I'll agree to that.
EDIT: although, there are scenarios where 2nd Sphinx can be better, specially if 2 of the top 3 cards are things you don't want.
Man, this is why is so hard to discuss stuff in this forum. Did I EVER say Sphinx is as good as Ponder? I said it's effect is more analogue to Ponder than to Preordain.
My analysis of the card is that it gives you a tempo/mana boost, allowing you to filter through your deck while keeping mana up. That's it. That can be very relevant, and requires more extensive testing to even see if having a 4 mana card stuck in hand is worth it (I'd say if you play with Dack and/or JVP it's pretty ok) and also the correct number of Sphinx in a given list (it's probably not 4).
I'll just point out the fact that Sphinx actually digs you FURTHER than ponder if you need it to. Ponder requires a shuffle before the draw, so there is a chance to redraw the stuff you shuffled. Sphinx keeps them on the bottom, which ensures your next draw (and even subsequent ones) are not those cards. If you are looking for a specific combo piece sphinx is much more efficient on turn 1 than ponder, but obviously that falls off after that.
@fsecco - I think the ideal number will be 4 for any number of reasons, but besides Maximizing the odds of having one in your opener, it also gives you the maximum ability to remove extra copies of itself from your top 3, which I know sounds counter intuitive but I think if youre trying to find one specific card with the sphinx maximizing that is the way to go.
@protoaddct You'll have to evaluate how often it's a dead draw for you, much like other "Leylines". Also I don't think the card is only applicable when you're looking for a combo, it's great when you want to make your next turns good. Imagine that Xerox scenario I wrote here, but you're playing against MUD. If you see a Volcanic and an Ancient Grudge on top, you're probably not going to spend your counters on their creatures, only FoWing their Sphere if they play one. The information it gives you is on par with Gitaxian Probe imo.