The Left Foreleg, as with the Right Foreleg and Long Gui itself, is vulnerable to Thunder-based attacks. At times, the Long Gui may use its Left Foreleg to execute the Stomp technique, which deals large amounts of damage to all party members who are on the ground.
As with the Right Foreleg, when it comes to depleting the Left Foreleg's HP, the party need only use the Relentless Assault Paradigm (COM/RAV/RAV). It is recommended that the party leader serve as the Commando; one must use physical attacks to start filling the Left Foreleg's Chain Gauge, while Thunder-based attacks from the two Ravagers in the party will ensure that the rest of the Chain Gauge fills swiftly. The process of filling the Left Foreleg's Chain Gauge can be further hastened through the use of Tri-disaster (RAV/RAV/RAV), but in the end, a combination of physical attacks and Thunder magic is all that is needed to conquer this mighty foe.