"Mammoth Umbra" is a creature enchantment card from the Magic: The Gathering Planechase Anthology set, classified as an Unknown rarity. Currently valued at $0.25, it provides a +3/+3 bonus and trample to the enchanted creature, making it a strategic choice for enhancing creature combat. Its market presence reflects a niche interest among collectors and players, often sought after for specific deck builds rather than broad appeal.