Thundara is a magic spell in Final Fantasy VII Rebirth. It is granted by either
Lightning Materia or Lightning and Wind Materia, and is the mid-tier 
Lightning-elemental spell above 
Thunder and below Thundaga. Thundara deals moderate lightning-elemental damage, with a medium MP cost and casting time. The spell causes a bolt to hit the targeted enemy.
Thundara is also used against the player by Experimental Varghidpolis, Hecteyes, Specimen H1024, Twin Brain, and Yin & Yang.
Use[]
Thundara costs 10 MP to cast with a level 2 lightning or lightning and wind materia equipped. The spell is effective broadly due to its reliable damage output, but is particularly strong against enemies that are weak to lightning (particularly mechanic enemies). Among its peers— Fira, Blizzara, and Aerora—Thundara's reliability in hitting targets makes it strong against single enemies, with a slight drawback in its area-of-effect damage.
Thundara outclasses Thunder in terms of damage output, but its MP cost means players may consider casting Thunder in many circumstances. Though Thundaga's damage output is much greater, its longer cast time, MP cost, and the fact it costs two ATB charges, means that Thundara will often be a better choice.
Thundara can be amplified by pairing its materia with 
Support Materia. HP Absorption Materia and MP Absorption Materia can increase a party member's sustainability, allowing the spell to heal the user or to be cast more frequently, respectively. Magic Focus Materia can increase the spell's damage against individual targets, and Magnify Materia can make for a powerful combination when it hits all enemies at once. Magic Efficiency Materia can reduce the spell's cost and Swiftcast Materia reduce its cast time, though these boosts better suit Thundaga than Thundara.
Using Thundara with Aerith's Arcane Ward will cast it twice. Further using Yuffie with Doppelganger when in Arcane Ward can cast Thundara four times, potentially overwhelming enemies.
If the party member casting Thundara has unlocked their lightning-elemental weapon ability (e.g. Rolling Thunder for Aerith), Thundara becomes Thundara α, which will bestow a lightning-elemental sphere to the spellcaster for the rest of the battle (unless the player changes the element with Fira α etc.) that will supplement small magical lightning-elemental damage when defending against certain enemy attacks (perfect-blocking not needed) and when using ATB abilities. The attacks from the "fire sphere" do build stagger and can be critical hits.