Calcium carbonate, a Rare card

The card carries these facts from its Wikipedia article.

• It is a common substance found in rocks as the minerals calcite and aragonite, most notably in chalk and limestone, eggshells, gastropod shells, shellfish skeletons and pearls.
• Materials containing much calcium carbonate or resembling it are described as calcareous.
• Naturally occurring calcium carbonate is important part of the carbon cycle, sequestering large amounts of carbon in geological formations.

Rarity in WikiCards follows a year of Wikipedia page views: the most read articles become Epic and Legendary cards. The Calcium carbonate article was read about 260,000 times in a year. ATK comes from the length of the article and DEF from its quality, so this card hits with 83 and blocks with 87: each hit it takes is cut by 35 %.

Open packs. Each pack holds five cards drawn from real Wikipedia articles, the rarest last, and the fifth card is always Rare or better. The odds are shown in the game. A free pack arrives every hour and two can wait, and the Coins you win in duels buy more packs.

The cards just above and just below Calcium carbonate in the power ranking, all domains together.