Flare II, along with the other of the Black Mage's second tier Ancient Magic spells, is learnable at level 75. Flare II's scroll can be bought from Susu in Lower Jeuno for 129,180 gil.
When used, Flare II deals massive fire damage to a single enemy and lowers its resistance against the water element for a period of 15 - 30 seconds. Due to the latter effect, Flare II can be easily be followed up with earth spells such as Waterja and Water VI.
Through Merit Points, Flare II's Magic Burst potency can be increased by 3%, while its magic accuracy can be increased by 5.
Behind the scenes
When originally introduced to the game, Flare II could only be learned by Black Mages level 75 and higher by spending 3 Merit Points to purchase it from the merit menu. Following the June 2019 patch update, Flare II was changed to become a purchasable spell in Lower Jueno.
flare is a pyrotechnical phenomenon that produces intense amounts of heat and energy that does not result in an explosion (an immediate release of energy).A
In the case of Final Fantasy, while this may seem weaker than an explosion, a flare is a contained release of energy, which fully exposes the enemy to the source rather than blow them away from it after a while.