Batman is obviously an on-topic character for our site. He regularly teams up with or confronts aliens and has awesome technology at his fingertips even if he himself is "just a man in a suit".
However, would that have always been the case? I know Batman debuted in "Detective Comics" in 1939 and was popular enough to gain his own comic series in 1940. Wikipedia states: "The early part of the era known to comics fans and historians as the Silver Age of Comic Books saw the Batman title dabble in science fiction."; with the Silver Age starting in 1956.
At any point between the debut in 1939 and the claim that science fiction dabbling didn't begin until ~1956 did Batman have any other element that would have been considered "science fiction" or "fantasy, and if so what was the first occurrence?
Note: I am performing a bit of hypothetical... if SFF.SE existed back in the 1940s, would Batman been considered on-topic, or would he been have like James Bond's "spy-fy" where the series at large would have been off-topic (at least until the introduction of the SFF elements)?