Nagashino Barricades

Nagashino Barricades enters the battlefield
tapped. If you control three or more riflemen
creatures, it enters untapped instead.
{t}, add {r} mana to your mana pool.
{1}{r}{r}, {t}, Nagashino barricade deals 2 damage
to each attacking or blocking creature
your opponents control. You can tap three
untapped riflemen rather than pay the mana.