Graviga

Graviga, also known as Quartr, Qrter, and Demi2, is a recurring spell from the series. It is a enhanced version of Gravity.

Final Fantasy V
Graviga, also known as Qrter and Demi2, is a Level 5 Time Magic spell which reduces the target's HP to roughly 1/8 for 18 MP. There is also a Blue Magic version called Level 4 Graviga, also known as L.4 Quarter.

Final Fantasy VI
Graviga, an Attack Magic spell also known as Quartr, reduces the HP of the entire enemy party by 3/4 for 48 MP. It is taught by Midgardsormr, as well as Diabolos in the Advance version, at a rate of x5.

Final Fantasy VII
Demi2 reduces one target's health to 1/2 of their current HP for 33 MP, and Demi3 reduces to 3/4 for 48. Both are spells contained in the Gravity Magic Materia.

Crisis Core -Final Fantasy VII-
Graviga reduces a enemy's HP by 1/2 regardless of its SPR for 40 MP. It is bought in the Bone Village Commerce.

Final Fantasy XI
Graviga is a spell that can only be cast by certain Notorious Monsters, which basically inflicts Weight in an area of effect. This spell is not available to learn by players, though a Scholar can simulate the effect with Manifestation (requires Red Mage to be set as a support job however).

Final Fantasy XII
Graviga is Arcane Magick 7 License. It reduces the health of an enemy by 1/2. In the International Zodiac Job System version, Graviga is a Time Magick 10 License.

There is also the enemy magick called Piercing Graviga, which is Graviga that ignores Reflect. It is one of a few Gravity spells since it can kill it's enemy if the HP is less than half.

Final Fantasy XII: Revenant Wings
Graviga is the normal attack of the Esper and enemy Zodiark. It deals damage equal to 25% of the target's HP.

Final Fantasy Tactics
Graviga, also known as Demi2, reduces HP by 3/4 for 50 MP and is learned by Time Mages. This spell is very effective against the Lucavi bosses due to them having no gravity defense and high HP totals. It has a speed of 12 and costs 550 JP to learn.

Final Fantasy Tactics Advance
Quarter is a spell reduces HP by 1/4 for 10 MP. It could be learned from the Force Rod. Demi, in a change from the norm, is stronger than Quarter and reduces HP by 1/2 for 24 MP. Time Mages can learn the skill from the Stardust Rod, and Babus knows the spell as the Runeseeker.

Final Fantasy Tactics A2: Grimoire of the Rift
Graviga, learned by Arcanist for 450 AP from the Stardust Rod, halves one enemy's HP. It requires 22 MP to cast, and has a range of 3.

Final Fantasy Crystal Chronicles: Ring of Fates
Graviga is casted by piling Fira +1, Blizzara +1, and Thundara +1. If it is cast on a player, he or she will not be able to jump for a long amount of time.

Final Fantasy Crystal Chronicles: Echoes of Time
Graviga is casted by stacking two Blizzard and two Raise target rings. It prevents the target from jumping for a long amount of time.

Dissidia Final Fantasy
Graviga is a Brave attack for Terra, in which she summons a large orb of dark energy above the opponent that descends to the ground.