Sorcerer in training
"Batman makes an oblique reference to having Kryptonite in reserve in Justic League: The New Frontier, when he warns J'onn J'onzz that he [Batman] knows his weakness [fire], too. Batman: I have a seventy-thousand dollar sliver of radioactive meteor to stop the one in Metropolis. With you, all I need is a penny for a book of matches."
In the graphic novel, the line was 'it took me a seventy-thousand sliver [etc] to take down the one in Metropolis.' Although later it's implied it was a fake out curb stomp. Also from the comic, Batman knew of J'onn's weakness because Batman was tracking down the crazy cult that kidnapped the child that 'John Jones' and his partner were trying to rescue.
And Wonder Woman is somewhat more... specific about what the Asian women she rescued went through.
Coming back to where you started is not the same as never leaving. -Terry Pratchett
I don't know if this is the right section to ask, but what's it called when a big bad has insurance on someone who is working from them (especially a hero/anti hero who has been forced)?