Meteor Javelin is best used just before the enemy is exiting their stagger period, due to the fact the Chain Gauge is reset after using it. It is also the best time as the Chain Gauge will be at the highest amount it could be, delivering the greatest amount of damage to the enemy. It is also extends the period of time that other allies can use attacks such as Smite or Scourge which deal a lot of damage to enemies exiting Stagger, for the use of a Full ATB Skill freezes the depletion of the Chain Gauge.