Brinebarrow, Vaults of Karfell

Brinebarrow, Vaults of Karfell enters the battlefield tapped unless you control three or more snow permanents.
{t}, Sacrifice a land: Add three mana of any type the sacrificed land could produce. Spend this mana only to cast snow spells or on costs that contain {s}.
Brinebarrow has all mana abilities of all land cards in all graveyards.
"Most who seek Brinebarrow don't return at all."
—Planeswalker's Guide to Kaldheim, Part II