Why Legends Of Tomorrow Needs To Keep John Constantine Around

Constantine and the Legends teamed up to try and free the young girl from Mallus, and they were all surprised to discover that young "Emily" was actually Nora, the daughter of Damien Darhk. Sara had to journey into darkness to save Emily (and solve the little issue of getting herself, Constantine, and Snart back from being sent to 1969), and it turns out that she didn't just emerge from that darkness. According to Constantine, a demon's power resides in Sara and it's only a matter of time before she succumbs to it. Constantine recommended keeping the Legends' anti-magic gun handy, and the good guys got a clue that six totems will play a part in defeating Mallus, but something tells me they're going to be in over their heads sooner rather than later. Sara is their leader, and she's not somebody who will be easily stopped if/when she turns on them.