As you cast this spell, you hurl a single slashing weapon at your foes, magically striking at all enemies along a line to the extent of the spell's range. You make a normal melee attack against each foe in the weapon's path, but you can choose to substitute your Intelligence or Charisma modifier (as appropriate for your spellcaster class) for your Strength modifier on the weapon's attack rolls and damage rolls. Even if your base attack bonus would normally give you multiple attack rolls, a whirling blade gets only one attack against each target. The weapon deals damage just as if you had swung it by hand, including any bonuses you might have from ability scores or feats.

No matter how many targets your weapon hits or misses, it instantly and unerringly returns to your hand after attempting the last of its attacks.