Umbra armor
Totem Armor is a keyword ability introduced in Rise of the Eldrazi. If a permanent enchanted by an Aura with totem armor would be destroyed, instead the Aura is destroyed. If that permanent is a creature, all damage is removed from that creature. In this sense totem armor works similar to Regeneration.
There are 10 aura cards with totem armor; green (4), white (3) and blue (3), all from the Rise of the Eldrazi set. In addition, the creature card Umbra Mystic can give the totem armor ability to auras.
All auras with totem armor have a two-word name, consisting of the name of an animal followed by the word 'Umbra'. The artwork of these cards (all illustrated by either Howard Lyon or Christopher Moeller) depicts a floating humanoid, surrounded by a glowing 'aura' in the color of the card and in shape of the animal the card is named after. For example, Bear Umbra depicts an elf surrounded by the glowing green figure of a bear, Hyena Umbra depicts a human surrounded by the glowing white figure of a hyena, and Eel Umbra depicts a merfolk surrounded by the glowing blue figure of an eel.
Totem-Guide Hartebeest, also from the Rise of the Eldrazi set, is a card that tutors for an aura. Although it's name links it to the totem armor auras, it can tutor for any aura card, not just ones with totem armor.
Reminder text
The latest reminder text for Totem Armor reads "If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura."