Land destruction at its cruelest. If your opponent can't stay ahead of the destruction, then they'll likely lose.
Most of the land destruction cards come with another option or effect--Some generate mana (Strip Mine, Ghost Quarter, and Seismic Spike). Some elect to destroy something else (Pillage and Wrecking Ball). Some provide a hasted creature (Avalanche Riders). Some cause extra damage to opponent (Roiling Terrain). Some provide future destruction targets (Ghost Quarter and Cleansing Wildfire).
The only land destruction spell that takes out a single land with no other effect will do so efficiently (Sinkhole).
The lands either provide or or are able to destroy lands.
Then there are cards to help the mana base- Chartooth Cougar, Dark Ritual, Sol Ring, and Talisman of Indulgence.
Lastly we have the artifact Dingus Egg which adds injury to insult.
The win condition is usually damage from the sparse few creatures so don't forget to pay the echo cost of Avalanche Riders or hard cast Chartooth Cougar when you have the mana. As a last alternate win condition use Dingus Egg and Roiling Terrain.
Sideboard: Most cards in the sideboard destroy even more lands. There are more creature options if you need them or even steal your opponent's creatures with Custody Battle. Lastly, Ruin Grinder was added for more mountaincycling, but the Menace and the Wheel of Fortune attached effect are nice also.
There isn't much contingency to plan for with this deck-- if the main deck strategy is failing altogether, then try a different deck.
List of upgraded cards-
