Arrow - Spoilers galore

The story arc for this season involves Star City attracting a ton of new vigilantes in the wake of everything that has happened. They've also already cast Wild Dog and Vigilante. I don't think it's anything Young Justice related with her being Artemis. Just a relevant name.

And I'd be supremely shocked if you saw Nightwing. Although with Superman officially showing up on Supergirl maybe those shackles are a bit looser than they used to be.