WARNING: SPOILERS/NSFW - DC on SCREEN #108 - Arrow 4x13 - Sins of the Father | Review - Nyssa is trying to blackmail Oliver into getting Malcolm to give up the ring of Ra's Al Ghul to her in exchange for an elixre derived from the blue lotus flower that was protected by Katana... sigh. Easier solution? Kill Malcolm!  Sure he's Thea's dad, and sure she's about to die and needs the lotus elixre, but when both Diggle AND Felicity tell you to kill Malcolm Merlin (who has caused you no end of grief over the years), you should probably just kill the bastard.  Right?  So here we are.  Wondering why Oliver didn't kill him.  And wondering why he never sees anything coming.