Negación

is the term describing the fields used by Hollows to rescue their comrades. Only the Gillian-class Menos have demonstrated the ability to use Negación.

Description
Negación are square fields that engulf the target in a towering beam of light that completely isolates them from the dimension they are currently in, making it impossible to harm them from the outside of the impenetrable pillar. The field then draws those within the interior towards the Menos that created it.

All Gillian-class Menos can use Negación, though it has only been exhibited if the target was outside of Hueco Mundo at the time (i.e. the Human World, etc.). The technique is used only to aid their fellow Hollow or comrades, as evidenced during Kaname Tōsen, Gin Ichimaru and Sōsuke Aizen's escape from Soul Society. In the course of this, Genryūsai Shigekuni Yamamoto stated that the moment that the beam of light surrounded them, it was over as they had gone beyond their reach, a fact known to anyone who had fought Gillian previously.