Gravira

Gravira (グラビラ, Gurabira), also known as Demi 2, is a stronger form of the spell Gravity in the Compilation of Final Fantasy VII. As a Gravity spell, it does damage to the target based on a percentage of its HP. It serves as the intermediate spell between Gravity and Graviga.

Final Fantasy VII
Demi2 reduces a target's health to 1/2 of their current HP for 33 MP and is the second level spell on the Gravity Materia. Only the boss Gorkii can use the spell against the player.

Before Crisis -Final Fantasy VII-
Gravira costs 50 MP to cast and does moderate Gravity-elemental damage to enemies.

Crisis Core -Final Fantasy VII-
Gravira is an ability exclusive to Movers. As with most Gravity spells, it does damage based on Zack's current HP.