If they ever do a Merlyn flashback...
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Malcolm Merlyn: You're vigilantes.
Ra's al Ghul: No, no, no. A vigilante is just a man lost in the scramble for his own gratification. He can be destroyed, or locked up. But if you make yourself more than just a man, if you devote yourself to an ideal, and if they can't stop you, then you become something else entirely.
Malcolm: Which is?
Ra's: Legend, Mr. Merlyn. Legend.
---
Season 5 on Lian Yu:
Laurel Lance: Why didn't you just... kill me?
Slade Wilson: You don't fear death... You welcome it. Your punishment must be more severe.
Laurel: Torture?
Slade: Yes. But not of your body... Of your soul.
Laurel: Where am I?
Slade: Home, where I learned the truth about despair, as will you. There's a reason why this prison is the worst hell on earth... Hope. Every man who has been stranded here over the centuries has looked out to the sea and imagined swimming to freedom. So easy... So simple... And like shipwrecked men turning to sea water from uncontrollable thirst, many have died trying. I learned here that there can be no true despair without hope. So, as I terrorize Starling, I will feed its people hope to poison their souls. I will let them believe they can survive so that you can watch them clamoring over each other to stay in the sun. You can watch me torture an entire city and when you have truly understood the depth of your failure, I will fulfill Shado's destiny... I will destroy Starling and then, when it is done and Starling is ashes... then you have my permission to die.
I couldn't think of a new villain outside of Slade or Bane that this piece of dialogue would work for.
But man, imagine if Laurel got stranded on Lian yu