Pathfinder, Foward Scout

Metalcraft-This spell costs {1} less to cast per
artifact you control.
{1}: Pathfinder, Forward Scout gains reach until
end of turn.
{3}:Target creature can't block until that player's
next upkeep.
Tap 3 artifacts: Draw a card.
Tap 6 artifacts: Search your library for an artifact,
then cast it without paying its mana cost.