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Squall's Junction screen.

The Junction System is a technology and skill system in Final Fantasy VIII.

The Junction System is a device that allows the user to replicate the powers of a Sorceress via the storage and control of magical powers and Guardian Forces. The system itself is capable of storing 32 different forms of Para-Magic with a stock of 100 units of each form.
The system acts as a type of filter, filtering out magic (known as Drawing) from a being or entity and storing it ready to be used or junctioned by the user. This allows the user to possess near superhuman abilities such as increased speed and strength as well as being able to use magic as a weapon. Various Junction Systems are seen in wide use in the military forces, particularly in SeeD.

Junctioning

Because general enemies in the game are always about the same level as the player's characters, simple leveling up of the characters does not help them gain the advantage over the enemy. Without utilizing the Junction System, characters will not be able to use abilities other than "Attack" during battle. Therefore, by junctioning Guardian Forces (GF) to the characters, the player can customize the characters, in terms of stat upgrading, ability commands that can be used in battle, and later on, what elemental and status ailment attack/resistances that character has. What precisely can be upgraded depends on the GFs that the player have junctioned, and what the GF has learned.

To upgrade any stat and/or attack/resistance, magic can be junctioned to the stat provided a GF junctioned to the character in question has learned the corresponding Junction ability. The more magic junctioned, the larger the effect.

In order to upgrade basic stats, for example, HP and Strength (Str), any magic can be used for junctioning, but some magic will have a larger effect on certain stats than others, for example, junctioning the "Haste" spell to the character speed stat boosts the speed of the character to a much larger degree than junctioning "Scan" or "Fire" to the speed stat.

Element and Status Effect Junctioning

Upgrading Elemental attacks/resistances (Elem-Atk/Elem-Def) (if the GF has learned the abilities) generally requires elemental magic. Junctioning "Fire" to an Elem-Def stat will increase a character's resistance to fire attacks, the larger the quantity of Fire magic there is junctioned, the higher the resistance. Some other magic will provide multiple resistances, notably "Ultima" will provide resistance for all elements. Junctioning elemental magic to the Elem-Atk stat will cause the character's normal "Attack" to posses some elemental property, giving advantages against some enemies, dependent on the element.

Similarly, upgrading Status Ailment attacks/resistances (ST-Atk/ST-Def) (if the GF has learned the abilities) generally requires magic that cause or cure status ailments. Junctioning Death to ST-Def will make a character resistant to "instant death" attacks, while Junctioning Death to ST-Atk will allow a character to cause "instant death" when executing a normal "Attack".

Players can choose to auto assign magic to Stats, Elem-Atk/Def and ST-Atk/Def by using the Auto command in the Junctioning menu. The player can auto assign magic giving priority to Strength, Magic or Defense.

Command Ability Junctioning

To use Command Abilities in battle (and in the case of Draw, in the field), characters require them to be "junctioned". Again, the abilities available depend on the GFs junctioned, but do not require magic to be junctioned. In the same way, to use the Character/Party support abilities that the GF has learned, they also require junctioning, but do not require magic.

Support Ability Junctioning

Other than action commands, passive abilities can be junctioned. A character starts out with two slots, but can eventually gain three, where party or ally-abilities can be junctioned. For example, if a GF has learned the ability HP+20%, it must be junctioned to one of the slots, for it to be activated.

Junction Values

Elemental

Status Defense