Jinny Hex was given a trunk that belonged to her great great great grandfather, Jonah Hex. It had been passed down generation to generation. In it was a cache of various weapons and tools both technologically superior to Jonah's time and mystical in nature. Jonah had collected them during his time as an adventurer, and now they belonged to Jinny.
Jinny becomes involved with the latest incarnation of the Young Justice team. As part of this, she's tossed through the multiverse, meets the adopted hero Naomi and becomes deeply involved with Cadmus Labs. This last part usually is a good thing for people in Jinny's situation, as Cadmus is deeply experienced with helping out powered heroes and their related dramatic situations. However Cadmus is no long trustworthy.