Chain

is a technique which Zangetsu can use after fully taking control of Ichigo Kurosaki's body.

Description
After transforming Ichigo's body into a fully Hollowfied form, Zangetsu can call his Zanpakutō to his hand with a simple gesture. This ability is due to the fact that Ichigo is connected to Tensa Zangetsu's severed chain through his reiatsu. As such, Zangetsu was able to call the Zanpakutō to him with ease; this is not a technique, but a power that Ichigo has.