In Arrow, not only is there a character called John Diggle but also he has a murdered brother called Andy, named after the writer of the Green Arrow Year One miniseries, thus another metafictional reference to an earlier continuity. In this and the previous two posts, we have referred to six continuities each featuring a different version of Oliver Queen:
Silver Age; The Dark Knight Returns; GAY1; Smallville; Arrow.
the four comic strip Olivers fought crime;
the DKR Ollie also fought the US by sinking a sub and helping Wayne against Kent;
the first screen version fights Luthorcorp;
the second fights the corrupt controllers of Starling City.