Price$10.62 – $27.76
Buy on TCGplayerSacred Foundry
Land — Mountain Plains
LegalEDHREC #78
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As this land enters, you may pay 2 life. If you don't, it enters tapped.
Why is this card good?
Sacred Foundry is the Boros shock land, and like all shock lands, it's premium fixing because it counts as both basic land types (Mountain and Plains). That typing is the real reason these are worth more than a Temple or tapland: it fetches off Arid Mesa, Flooded Strand, and any other land that grabs Mountains or Plains, and it synergizes with cards like Tithe, Farseek (no, Farseek can't grab it—Sacred Foundry is not a Forest/Island/Swamp/Mountain... actually it IS a Mountain), Hour of Promise, and domain effects.
The "pay 2 life to enter untapped" choice is what makes it elite: in Commander you can afford the life, and entering untapped on turn one keeps your curve honest in fast Boros decks.
Play it in any two-color Boros deck or any multicolor deck running red and white where you value untapped fixing and fetchability—aggro, tokens, equipment/voltron.
Skip it only on a tight budget; a tapland or Temple works if speed and life total don't matter.
Related cards
Clifftop Retreat
RW dual that enters untapped if you control another land type, same colors.
Inspiring Vantage
RW fastland, untapped early, same dual-color fixing.
Battlefield Forge
RW painland, always untapped colored mana for the same pair.
Sunbaked Canyon
RW horizon land cycling, untapped fixing.
Rugged Prairie
RW filter land, flexible colored mana.
Plateau
Original RW dual land, untapped with both basic types.
Sundown Pass
RW slow dual, untapped fixing for Boros decks.