Horus, The Balance

Horus, The Balance makes all of your Creatures'
abilities that involve you gaining Mana or your
opponent losing Mana ignore Armor.
{1} [Harmony, Discord] — You may use this
ability whenever a Creature effect is activated.
You may place one "Harmony Orb" counter on
one of your Creatures, or one "Discord Orb"
counter on one of your opponent's Creatures.