He said: "That's a really difficult question to answer because it's very, very difficult for me to look back at what we've done in the series from the equivalent of 30,000 feet when I'm deep in the middle of it. I guess the proof is in the pudding, if you know what I mean? You've now got 'Arrow' and 'The Flash', as well as 'Legends', 'Supergirl' and 'Black Lightning'.