The Narayanastra () (or Narainastra) was the personal weapon of Lord Vishnu in his Narayana form. This astra (weapon in Sanskrit) in turn fires a powerful tirade of millions of deadly missiles simultaneously. The intensity of the shower rises with increase in resistance. The only way to defend against the missile is to show total submission before the missiles hit, this in turn will cause this weapon to stop and spare the target. It is one of the six 'Mantramukta' weapons that cannot be resisted.