Does armor prevent non-combat damage?
ARMOR
Some creatures have an armor value to the right of the card title. Armor prevents an amount of damage equal to the armor value that the creature would take each turn. For example, if a creature has two armor and is dealt one damage, that damage is absorbed by the armor, leaving the creature with one armor for the rest of the turn. If the creature is later dealt three more damage during that turn, one damage is absorbed and the other two damage are dealt to that creature.
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It absorbs all forms of damage, not just damage resulting from combat.
Note that the armor value is the amount of damage that is absorbed per turn, not per damage event.