The Mightstone and Weakstone [The Brothers' War Prerelease Promos] Tribal Artifact Criosphinx Sovereign or another Sphinx

Criosphinx Sovereign or another Sphinx enters the battlefield under your control

Rather than sheltering her young

”—Saffi Eriksdotter

That player may search their library for that many basic land cards

The Mightstone and Weakstone [The Brothers' War Prerelease Promos] Tribal Artifact Criosphinx Sovereign or another SphinxSet: The Brothers' War Prerelease Promos Type: Legendary Artifact Powerstone Rarity: Rare Cost: {5} When The Mightstone and Weakstone enters the battlefield, choose one Draw two cards. Target creature gets 5 5 until end of turn. {T}: Add {C}{C}. This mana can't be spent to cast nonartifact spells. (Melds with Urza, Lord Protector.)