Cometeor is a magic spell in Final Fantasy VII Rebirth. It is granted by the 
Comet Materia, and is the higher-level comet spell above 
Comet. It is the strongest non-elemental magic spell in the game, and fires a number of comets in an area around the targeted enemy, dealing immense damage overall. However, the spell is hindered by its high MP cost and very lengthy cast time.
Use[]
Cometeor can be used when a fully leveled comet materia is equipped. The spell deals immense damage that is spread across multiple comets firing in an area. This gives it great area-of-effect damage, but also powerful damage against a larger target in total. Though the damage output is the highest of any spell, its MP cost and lengthy cast time are prohibitive and mean it should be used rarely.
Cometeor's non-elemental damage means it is effective against all enemies types regardless of elemental weakness. It also means that, against enemies with an elemental weakness, it is still more efficient to target them with a spell against their weakness. If players wish to avoid the long cast time and are fine with hitting a single target, Quaga is a suitable alternative.
Cometeor is at its best when its shortcomings are alleviated by the 
Swiftcast Materia, which can eliminate its lengthy cast time. However, some players may prefer to pair swiftcast with other materia depending on need.
Among other Support Materia to benefit Cometeor, Magic Efficiency Materia is the most effective, reducing its prohibitive MP cost. HP Absorption Materia and MP Absorption Materia can improve a party member's sustainability, but do not significantly reduce the spell's shortcomings and suffer due to the spell's lack of reliable damage to one target (as its comets spread across an area). Magic Focus Materia can increase the spell's power, but this is hardly an area the spell is lacking. Magnify Materia is effectively redundant as the spell already has a great area-of-effect.
Using Cometeor with Aerith's Arcane Ward will cast it twice. Further, using Yuffie with Doppelganger when in Arcane Ward can cast Cometeor four times, potentially overwhelming enemies. If this is done, it is best to use swiftcast. Spellcasting on Radiant Ward makes the caster immune while casting; Cometeor is potentially good for this setup.