What is Foul?

[Iscah]

I think Flare makes more sense as the anti-Holy - both learned at Lv50, and paired up as RDM's Verflare/Verholy finisher spells.

[Jonnycbad]

I think Flare makes more sense as the anti-Holy - both learned at Lv50, and paired up as RDM's Verflare/Verholy finisher spells.

Flare is learned at level 50, Holy is learned at level 45. According to the Lore book, Verholy and Verflare don't share THAT much in common with the original spells other than being namesakes.

Flare: Shanttoto the matriarch of black magic, derived this spell in her reckless pursuit of ultimate destructive power. Combining one's own mana with ambient aether, the caster triggers an explosion of monumental force.

Holy:This incandescent blast of purifying energies was devised by the white mages of Amdapor to combat the voidsent servants of Mhachi sorcerers. The battlefields of the War of the Magi were often illuminated by spell's distinctive explosions

Verflare: Its name is a portmanteau of "vermillion" and "flare". This incantation seeks to rival the destructive power of the black mage spell that shares the latter's denomination. Rather than drawing on ambient aether to cause a single, massive explosion, Verflare overlaps a number of smaller arcane eruptions.

Verholy: An adaption of the forbidden white mage spell "Holy", this purifying blast was conceived as a means to banish the lingering voidsent, which were summoned during the War of the Magi

So Flare combines the user's mana with ambient aether to make a gigantic explosion. Holy is a purifying blast of light energy to wipe out low level voidsent. Verflare uses a chain of small microexplosions instead of using ambient aether to make a localized magical burst. Verholy is a singular blast of "holy". It's more concentrated and the description says it was used to pick off individual voidsent survivors after the war, as opposed to the WHM version which was probably used against hoards/armies.