Auras were occasionally surprisingly good, even
long before the totem armor and bestow keywords.
Armadillo Cloak has Pro Tour pedigree - it
propelled Rith the Awakener to ridiculous
airborne attacks back in 2000, and still turns
any creature into a must-answer threat. And it
has some of the coolest flavor of any aura, of
any time. How often do you get to defeat an
opponent via the concept of your creature
rolling over the opposition like the armadillos
in Donkey Kong Country?
It works indeed. If you can drop this on a
creature of any meaningful size and swing even
once without eating a removal spell, the
resultant life swing can turn a game around.
Auras from The Good Old Days didn't usually make
headlines, since their baked-in card
disadvantage was just too... disadvantageous,
but this effect was worth opening up the
possibility of getting 2-for-1'd. In Limited,
it's an "answer me now or lose" card, and in
Constructed, it can break open stalemates. Sure,
sometimes your opponent had the answer in hand,
but you can't live in fear of what your opponent
may or may not have. If you don't press the
attack, then that's even worse than having your
spells countered because they didn't have to
expend resources to stop you.