The Link System (リンク システム, Rinku Shisutemu), colloquially called a Link (リンク, Rinku), is a concept introduced through Dragon Ball FighterZ. It is the phenomenon of souls — both artificially created and natural — possessing another body through artificial means.
When a soul is linked to another body through linking, it is near functionally the same to the Body Change, or other methods of exchanging bodies, only the original soul is suppressed into unconsciousness. From there, the power of the body is itself weakened, leaving them unable to access certain complex techniques. The soul that possesses the body however, appears to control the bulk of the power; when a soul possessed Gokū, it was capable of using his body to become a Super Saiyan, while Gokū could not transform, due to the Surge permeating Earth. This effect gradually lessens.
A linked soul is capable of bonding with their host's original soul; doing this draws out more and more of the original bodies' full strength. They can communicate telepathically, with whichever person isn't in control communicating from within their mind. A linked soul is also able to pass control over to their original host if they choose.
A reverse situation is also true; the soul within the body can be suppressed by the host, bending the linked soul to their will. This allows them to tap into more of their true power in the same way bonding with a soul would.
A link is not always possible, and can very well fail. Lapis was the subject of a link in the bid to help No. 21, but his body rejected the artificial soul. Several other test subjects failed to successfully Link. The Earthling Soul is the first known example of a compatible living soul. Even if a Link succeeds, a soul is not typically able to remain out of its body for extended periods, and usually return to their bodies within a minute. The Earthling Soul is the only known exception.
- The concept used for Link System to introduce the player to the events of the game using his "soul" in the body of another character is something already used in other games.
- In Bravely Default the player is a celestial being, where his soul resides in the body of Tiz Arrior, effectively keeping him alive and giving him abilities manipulated by the game's options (Example, decrease the rate for the random battle).
- In Undertale the main character Frisk can have they actions manipulated by another soul (officially called "Chara"), who represents the player at some degree.
- It also bears similaries to the Naruto series, and how a Jinchūriki bonds with their Tailed Beast to obtain further strength.