Treasure Cruise never inspired me. It's the kind of card that you play with once, recognize how broken it is, and figure out how to make the most efficient use of it you possibly can. Within a week of the realization that Cruise is broken-good, lists abusing the card in a Delver of Secrets shell were everywhere, and players were staring down Cruise mirrors left and right.
An endless sea of mirror matches is not the kind of Magic I'm looking to play. Often this leads me to choose decks that others would cite as "not the best deck," but I value my own time and personal experiences highly, and if I choose to play a deck I consider the best in a given format, but I don't enjoy playing it, I'm throwing away a large portion of what brought me to an event and the game in the first place. I'm a subscriber to the idea that there is very rarely a de-facto "best deck" in any environment, but rather a spectrum of decks that are highly competitive; and the individual who is piloting the deck has a significant contribution to the value of the deck itself. In other words, pick the deck that's best for you out of the group of decks that comprise the best in the field.
In Legacy, this ultimately means you end up choosing something powerful, and doing that powerful thing until someone stops you. Of course with a card pool as deep as Legacy's, there are any number of powerful things to do and deciding which angle you want to attack from has always been the key decision.
Prior to Grand Prix New Jersey last year, I took a good hard look at the format – because it had been so long since I had played any Legacy (a topic for another time), I could approach the format with a new perspective. My impression was that while many decks were clamoring to be the best Treasure Cruise deck, there was one deck that stood out to me as the best Dig Through Time deck and I was fairly certain that's where I wanted to be.
Unlike Cruise's Brute Force card advantage, Dig Through Time represents a tool utilized to find specific puzzle pieces. This type of card selection plays more directly into my wheelhouse as a deck builder and I was much more inspired by the idea of looking seven cards down than I was by drawing three. I saw how well this seemed to fit into a deck filled with as many cantrips as I could muster, and picked the combo deck that seemed to buy the greatest benefit from this. I tossed together a rough draft of OmniTell with Dig Through Time and started goldfishing games.
What I quickly recognized was not only does DTT offer OmniTell a significant advantage in finding and assembling its key combo pieces, the card actually represents a strong part of the combo engine in itself - largely supplanting the need for Enter the Infinite to combo off with. The list I (admittedly) poached from a recent SCG Open prior to DTT becoming legal ran three Enter the Infinite in its maindeck, the requisite number to be Intuitioned for. I began shaving the numbers almost immediately, and realized that if you want any at all, you only need a single copy for backup; Dig Through Time was essentially all the combo you need. You cantrip and Dig until you find an expensive card and a Brainstorm, then use the Brainstorm to put an 8+ CMC spell on top of your library. This is effectively the same thing you do with Enter the Infinite, but there's no real need to draw your whole deck if you can set up the top card to win via Release the Ants. Dig Through Time allows you to do with a fair amount of triviality. Interestingly, the Digs also allow the maindeck to function similarly to the sideboard. In the same way that Cunning Wish gives you access to a large array of powerful but situational effects, Dig allows you see so many cards in a given game that access to some number of powerful one-ofs in the maindeck is reasonable and boarding in Wish targets becomes a realistic prospect since you have a good probability of finding them in either zone.
The more I played the deck, the more impressed I became, and I eventually brought a list to Grand Prix New Jersey, where I ran into a few unfortunate instances and was eliminated during the last round of day one. Sometimes your opponent draws Reclamation Sage as his one draw before you put Omniscience in play. Magic: The Gathering.
Fortunately, it appears I was on the right track despite my anecdotal evidence to the contrary, as Akash Naidu piloted a very similar list to my own into a 9th place finish at that event. I noticed that Akash's list incorporated a few changes I had discussed making on the ride home from Jersey, and includes most of the major pieces I feel are necessary to discuss the decklist.
My personal changes to this list include the following.
Maindeck:-1 Pact of Negation
-1 Cunning Wish
+1 Dream Halls
-1 Dream Halls
-1 Eladamri's Call-1 Surgical Extraction
-1 Sapphire Charm
+1 Elesh Norn, Grand Cenobite
+1 Abrupt Decay
+1 Hurkyl's Recall
Because of the shift in the format in the wake of the Treasure Cruise ban, there's a shift away from counter magic as the primary mode of interaction with combo decks. That's not to say that decks like Delver don't exist anymore without Treasure Cruise, but they are nowhere near as prevalent as they were, and we aren't forced to Overload the maindeck with protection from maindeck Red Elemental Blasts. In the list I ran in Jersey, I slotted the full 16 one-mana cantrips (Brainstorm, Ponder, Preordain, Gitaxian Probe), and was very happy with the full suite. Akash's list runs an Impulse in the place of the fourth Preordain, due to the interaction with Firemind's Foresight (a card which I unfortunately neglected to play in my sideboard, and regretted), but I feel that you can afford the Impulse even with the full 16 cantrips. Additionally, Intuition provided an invaluable resource when combo-ing off, as it allows you to search up Emrakul, Dig, Dig, ending up with a Dig and a free reload on all the cantrips you've expended so far. Of course it also represents a tutor for missing combo pieces, which is a boon in many grindy matchups. The Dream Halls is shifted to the maindeck as a fifth copy of Omniscience, purely to add to your potential for combo-ing, and as an out to things like Meddling Mage on Show and Tell or a three drop floated on a Counterbalance.
In the board, I've cut the spells that my experience has shown to be redundant or un-needed, and have added a bunch I feel are particularly relevant in today's meta. The Intuition goes in as a Cunning Wish target draw spell to supplement the Firemind's Foresight, and as a tutor that can be cast when you're flush with Wishes but dry on combo pieces. Yes, it takes some time to set up, but there are a limited number of spells that can find both Show and Tell and Omniscience. For what it's worth, I strongly disagree with the idea of boarding a Dig Through Time to Wish for, as having the full set in the maindeck gives you the most potential to draw them and the most velocity when digging for combo pieces.
Elesh Norn is a direct response to a pair of my losses in New Jersey – one to Elves, another to Death and Taxes, where I could very easily have resolved a Show and Tell but was unable to combo out once I did for various reasons. Access to a card like Elesh Norn or even Massacre Wurm would have been a great boon, as it both answers the problem permanents from each weenie deck and represents a clock in itself. Most decks won't board Containment Priest in against you, as it's quite rare that you'd Show and Tell in Emrakul, so you're more likely to catch them off guard with this than a deck like Sneak and Show would be.
Abrupt Decay and Hurkyl's Recall are both a reaction to the metagame shift, as the hate has become more permanent-based than stack-based. Abrupt Decay allows you to win through a Counterbalance in a much more efficient manner, and can be boarded in to find via Dig and Cantrips to avoid the issue with Counterbalance + 3 mana spell. Hurkyl's Recall, though admittedly fantastic against Affinity, is specifically intended to be a response to the way decks like Lands and MUD attack your game plan. No matter how many Sphere of Resistance or Chalice of the Void (on one) they manage to resolve, you can always get them to pick up their football and go home. As long as you're prepared to handle a 20/20 flying indestructible Marit Lage Token, you're simply looking to buy time to set yourself up to win. If you're particularly concerned with the Lands matchup, you could potentially get away with running one to two Back to Basics in the sideboard, as that card has been known to do some damage to Lands and it's particularly synergistic to your manabase.
What really intrigues me about OmniTell is that despite the fact that Dig Through Time was banned in Modern specifically to eliminate the potential for it replacing Cruise in decks that want the effect; it was left untouched in Legacy – the format with much more powerful individual spells and three times the number of commonly-played cantrips. In the wake of the loss of Cruise, the lasting presence of DTT will be overlooked by many Legacy players, as they mistakenly believe the second blue mana in the cost to be a severe impediment. The power of Dig can't be denied, and I strongly feel this deck to be the most synergistic home for the spell. With the reduction of Red Blasts in the format, and the subsequent shift toward black-based hand disruption and permanent-based hate as the primary means of interaction with a combo deck, a spell like Dig Though Time – one that provides card advantage and selection at once, that has a flexible mana cost to play through Spheres and Thalia, Guardian of Thraben with ease – becomes even better than it was when its primary purpose was simply to see as many cards as possible, as fast as possible (which it still does admirably).
Even in the face of the resurgence of Sneak and Show (the arguably "better" Show and Tell deck), I would advise you to consider this monoblue beast instead. It has similar matchups to that deck in many regards, and has a fantastic Sneak and Show matchup itself. While it is more complex in its attempts to win, it has the distinct advantage of being capable of ignoring large portions of the metagame, and operating on its own plane of interaction. These are the things I'm looking for in a combo deck. Paired with the flexibility afforded by the inherent advantage granted by Dig Through Time, a Wish board, and "All your spells are free," we have a recipe for a strong (if currently underrated) competitor.