A while back, I wrote an article advocating for players to put more lands into their decks. Today's deck's designer really took that message to heart because they are playing a whopping 42 lands. That's the same number that the original Lands deck in Legacy ran, and even they've cut down a few over the years.
But here the land count is rather appropriate because each one is very likely a Shock, as the rest of the cards include four copies of Seismic Assault and three of Molten Vortex. You can combine either of these effects with Swans of Bryn Argoll to create an easy draw engine. The combo with Seismic Assault is so powerful that you will often draw enough extra lands to end the game on the spot.
Should you not be so lucky, Treasure Hunt can prime the pumps quite effectively, drawing about 2.4 cards on average. Or you can go big with Day's Undoing, mitigating the downside of ending the turn with the ability to throw a few Shocks around so you don't fall too far behind.
We've seen these pieces put together before, especially the combo of Swans of Bryn Argoll and Seismic Assault, but it's only recently that we've had this level of redundancy, to the point where you're not including any sub-par cards in the maindeck. Every card is a cog in the engine or a Swan Song, the most efficient way to protect an engine that can answer 2/2 fliers when it's unplugged.
You might expect a ridiculous number of basics with such a high land count, but there are enough utility lands and multicolor lands to make the manabase work double duty. The acceleration from Gemstone Caverns and the mana fixing from Cascade Bluffs for your RRR enchantment are the most important of the bunch, but don't underestimate the scry from Temple of Enlightenment or the occasional attack from Wandering Fumarole.
After sideboarding you get a little bit more interactive, and the easy part is that you can trim lands without hurting your core that much, especially Gemstone Caverns when you're on the play. You won't be as explosive, but you'll be a lot more resilient with some targeted disruption, and as the game goes long, your redundancy should take over, even with an increased land count.