Siege Modification is a uncommon Enchantment — Aura card from Magic: The Gathering (Aether Revolt, AER). Current market price: $0.30.
Uncommon
Aether Revolt (AER)
{1}{R}{R}
Mana Value
3
Colors
R
Card Text
Enchant creature or Vehicle
As long as enchanted permanent is a Vehicle, it's a creature in addition to its other types.
Enchanted creature gets +3/+0 and has first strike.
