With the right build, you draw enough fast mana, tutors, and protection to assemble a deterministic win immediately
It requires another card to make you become the monarch, which isn't great
Still, cast-from-exile decks have come a long way, and a protection spell that interacts with those synergies has its place
Here's an example of an Extended, Borderless, Full Art KTK Mountain: As you might imagine, it can be tricky to find good artwork that fits a 600DPI card, if you're looking to use official art
Its ability to fetch any two lands from the deck upon entering the battlefield has made it infamous for enabling powerful combosthink Dark Depths and Thespians Stage or Cabal Coffers and Urborg, Tomb of Yawgmoth
These let you dictate the pace or even close out the game