If Andúril is equipped to a creature an opponent controls, Andúril's controller will create two tapped Spirit tokens each time that creature attacks. Even if that creature is legendary, the Spirits would not enter the battlefield attacking.

If the equipped creature is legendary, Andúril's controller chooses which player, planeswalker, or battle the Spirit tokens are attacking. Each Spirit token can enter attacking a different player, planeswalker, or battle, and they don't need to be the same player, planeswalker, or battle that the equipped creature is attacking.