Thundaga (Final Fantasy IX)

Thundaga is a Blk Mag spell for Vivi in Final Fantasy IX that deals major Lightning-elemental damage to one or multiple enemies. The spell is missable, as it is learned only from one weapon that is only available for a limited time.
If Steiner and Vivi are in the same party (and neither is incapacitated in some manner), the former can also use Vivi's Thundaga spell in his sword magic, where the ability uses his stats rather than Vivi's. In Trance, Vivi can use the spell twice in one turn.
Abadon, Earth Guardian, Grand Dragon, Kuja, Malboro, and Necron can all cast the Thundaga spell. It can be reflected as normal and can be countered with the support ability Return Magic.
==Obtain==
Thundaga is learned from the Octagon Rod, bought from Daguerreo and Esto Gaza after the events at Desert Palace, up until the party enters the Shimmering Island portal. If the player misses buying the rod when it is available, Vivi cannot learn his third tier elemental spells.
==Mechanics== 
Black Magic spells are based on Vivi's Level, Magic stats, and the Spell Power of the spell. Vivi can use the Focus ability to increase his Magic during that battle by 25% per use. The effect stacks up to 99 and lasts for the entire battle, even if KO'd.
:Base = 72 - Target's Magic Defense
:Bonus = Magic + RndMOD ([(Level + Magic) / 8] + 1)
:Damage = Base * Bonus
Where Rnd means a random number, while MOD means modulus operation. "Rnd MOD x" can be read as a random number between 0 and x-1.
Bonus is halved by target's Shell, Vivi being under Mini, and if the player multi-targets the spell. Bonus is boosted by 50% if Vivi equips Flash Hat, or if Steiner equips Thunder Gloves for his Swd Mag.
In Vivi's Trance, Blk Mag turns into Dbl Blk where Vivi can cast two spells on his turn. The spells cost MP and expend the Trance gauge independently.
The support abilities that affect Thundaga are Reflect-Null (Thundaga pierces target's Reflect), Reflectx2 (Thundaga deals more damage when reflected), and Mag Elem Null (Thundaga deals non-elemental damage). 
For Swd Mag, damage dealt is based on Steiner's Attack and Strength stats, as well as on the power of the spell.
The damage formula for Swd Mag spells is as follows:
:Base = Attack + 72 - Enemy Defense
:Bonus = Strength + RndMOD ([(Level + Strength) / 8] + 1)
:Damage = Base * Bonus
==Use==
Thundaga is Vivi's third tier lightning spell and useful until the endgame. He can boost its power with Focus. It is especially good against enemies weak to the Thunder element, such as Quale and Kraken. Aquatic enemies are commonly weak to Thunder.
As a Swd Mag, Steiner can use it effectively against enemies weak to Thunder-elemental damage. Though it can also be used generally as a straight boost to his damage output, given Steiner's much lower MP pool, he should use it less regularly than Vivi. Using a Swd Mag tuned to the enemy's elemental weakness is more MP-efficient than Shock, but may be near equally powerful.
Category:Black Magic in Final Fantasy IX