Land and Sea is a green/blue Legacy lands deck that I designed with some very specific goals in mind. First, I wanted to design a deck that had the same or similar strategy as red/green lands, but that was less reliant on the graveyard in order to function. The main difference, other than moving from green/red to green/blue, is that I use Treasure Hunt as my main draw engine. In a deck that runs just over 2/3 of its cards as lands, this means that Treasure Hunt will draw on average 2 to 3 cards per casting without needing the graveyard to replenish your hand.
Some of the cards that a blue variant allows include Halimar Depths (which is powerful enough in its own right, but also combos considerably well with Treasure Hunt), as well as Tolaria West. I find Tolaria West to be an incredibly valuable, versatile, and powerful card in this deck, as it functions as an un-counterable tutor that is immune to Thoughtseize and Duress and that is quite often accessible by turn 2.
One of the things to immediately notice about this build is that it avoids running 4 copies of almost every card, with the exception of Treasure Hunt and Exploration. This makes the deck slightly weaker against glass cannon decks such as Tin-Fins or Storm on game 1 (mainly due to the reduced number of Crop Rotation), but places significant advantage in games 2 and 3, because you will be using Treasure Hunt to constantly be drawing into your best sideboard hate spells against those particular decks. What the deck loses in terms of early protection in game 1 it makes up for in an extremely aggressive land destruction strategy, running 4 Wasteland, 3 Ghost Quarter, and 3 Rishadan Port, which is devastating for all 2-color or more decks that are not running almost exclusively basic lands. The deck also runs 3 copies of Drop of Honey to take on the majority of creature-based decks, including Death and Taxes, Delver, Infect, and Shardless BUG, while also offering protection against Show and Tell if the opponent chooses to play a creature such as Emrakul, the Aeons Torn.
I've also included Ancestral Knowledge in the maybe board, as this looks to be a powerful combo with Treasure Hunt. I'll have to playtest it a bit before adding it to the main deck, but it looks very promising.
Deck Breakdown
Lands
Other than the lands that speak for themselves, I have the following breakdown of the lands I've included and why.
Boseiju, Who Shelters All: a 1-of that ensures that your Treasure Hunt and Regrowth will make it through, in addition to insuring that Seeds of Innocence will resolve in game 2 after your opponent has boarded in his 900 copies of Pithing Needle and Ensnaring Bridge.
Dark Depths: I run only 2 copies, because it is actually bad to get too many of these in your opening hand. Tolaria West will find one for you, no problem.
3x Ghost Quarter: A seriously underrated card in legacy! This card can destroy basic lands, and because most multi-color decks only run a few, this card can be used to destroy their basics in the early game while Wasteland takes care of the rest.
4x Halimar Depths: Another seriously underrated card. The ability of this land to dig for what you need is why you can get away with so few copies of individual spells in the main board.
3x Tolaria West: This card is simply amazing in this deck.
Spells
2x Crop Rotation: Easily the most controversial 2-of in the deck. The reason I don't run 4 copies in the main build is simply because getting multiple copies of this in your opening hand can lose you the game against some decks, mainly due to the fact that you 2-for-1 yourself every time you cast it. An extra copy is in the sideboard for when it's really appropriate, such as when you are up against Storm and Tin-Fins type decks, where you need to be dropping your land hate at instant speed.
3x Drop of Honey: This non-targeted creature hate spell is the perfect form of removal for this deck. It destroys 1 creature per turn until their board is clear or until they remove it. You can even reveal it when your opponent casts Show and Tell to kill whatever creature they cheat into play. This obviously will be boarded out for counter-magic games 2 and 3 if the opponent is not running creatures.
1x Life from the Loam: I only run 1 of these because it will often only be needed in specific circumstances, such as when your opponent is playing Death and Taxes or Miracles, where your Marit Lage keeps getting exiled.
2x Regrowth: A powerful and versatile spell that can bring back anything you need from the graveyard. This is a seriously underrated Legacy card.
4x Treasure Hunt: The bread and butter of this deck. Without needing to do anything, the card is on average a draw-2 or draw-3 for 2 mana. No setup required, no drawbacks, just pure 2 mana card draw. If you're not impressed with that now, maybe you will be when you draw your first chain of 6 lands and refill your entire hand for only 2 mana.
Sideboard
The sideboard is where this deck really shines. The reason is because once you board in, you will constantly be drawing your hate at a faster pace than your opponent. Treasure Hunt will not stop until you get a spell, and Halimar Depths can be used to dig for more answers, so the hate just keeps flowing. The sideboard's main focus is against decks such as Tin-Fins, Storm, as well as to include some answers to the predictable hate that your opponent will be boarding in (Pithing Needle, anyone?).
1x Multani, Yavimaya's Avatar: Alternate win condition.
1x Chill: red...
1x Crop Rotation: An additional copy is included in case of facing decks where Bojuka Bog, Glacial Chasm, or Karakas will be essential to bring out early.
1x Steely Resolve: Name Avatar to protect your Marit Lage or Multani from Karakas and Swords to Plowshares.
2x Flusterstorm: One of the main reasons why I wanted to make the deck blue.
1x Krosan Grip: in case they run Chalice of the Void
1x Null Rod: Simple, unimprovable artifact hate.
2x Pithing Needle: One of the most powerful cards in Magic: The Gathering.
1x Seeds of Innocence: A mandatory board-in game 2. Your opponent is going to be boarding in Pithing Needles and other trash. Don't say I didn't warn you.
1x Spell Pierce: This can be used to counter more unusual spell types like artifact or enchantments.
3x Surgical Extraction: Kills Tin-Fins dead.
