What is the blue glow around trunks SSJ2?


Is it some sort of pre-God Ki that is going to eventually transcend him to the
level of a God? And how was he able to even remotely fight black after Goku
and his dad were already defeated?




There is no official explanation, but manga #24 has given a very important
hint that can possibly be the answer (spoiler)

> Trunks is officially a kaioshin apprentice, he can use kibito technique to
> heal other people, and since kaioshins have god ki, as kaioshin apprentice
> he probably has some grade of knowledge on god ki.

