The World Tree - Promo Pack (PKHM) from Kaldheim, available at 401 Games Canada.

• Rarity: Rare
• Finish: Normal
• Artist: Anastasia Ovchinnikova
• Card Text:
  The World Tree enters the battlefield tapped.
  T: Add G.
  As long as you control six or more lands, lands you control have "T: Add one mana of any color."
  WWUUBBRRGG, T, Sacrifice The World Tree: Search your library for any number of God cards, put them onto the battlefield, then shuffle your library.