So, okay... pre-Crisis, Zod was a corporeal, living Kryptonian that Superman battled and defeated in the past (and killed, according to Winn, but I choose not to believe that). But now he's just a mind in the Eradicator, which would suggest he died on Krypton and never came to Earth. Unless the minds in the Eradicator are just copies, I guess.
There were too many characters named John in this episode -- Jon Kent, John Henry Irons, John Diggle. It got confusing once or twice. At least The Flash keeps its two Noras in separate story arcs. Diggle's inclusion did feel a little disconnected from the overall story, and didn't really advance the arc he's supposed to be having through these guest appearances, aside from a throwaway reference to being done with "glowing boxes" and the like. I guess we have to wait for his Supergirl appearance to see any more of that.
If they were going to include Diggle and finally acknowledge the wider Arrowverse in this one, I wish they'd also thrown in a reference to seeking Supergirl's help with finding Superman. I get the show wanting to establish its own independent identity, but if they're finally making connections, then they should be consistent about it.
