5) Lady Shiva
Arrow has retooled many Batman villains to go up against the titular hero already – Ra’s al-Ghul, Deathstroke, Huntress, Deadshot, Firefly – there was even a cameo from Harley Quinn! She might not be as well-known as most of those names, then, but Lady Shiva would make for a fantastic addition to the Emerald Archer’s rogues gallery.
Shiva is said to be one of the deadliest assassins and THE most adept martial artist in the whole of the DC universe. In the comics, even Batman has admitted that she’s a better fighter than him. Like Cheshire, she could be easily brought into the show due to her connections with the League of Assassins but, more than any other assassin Oliver Queen has faced, Shiva would really test his mettle.
To be honest, it’s so odd that the character hasn’t appeared in the show yet that it suggests the Arrow team don’t have the rights to her. That said, we haven’t heard about Shiva making an appearance in the DCEU anytime soon, either. If The CW do have the ability to use the character – Shiva did turn up on the network’s Birds of Prey many years ago – but aren’t doing anything with her, they need to sort that out fast.