Directed by Chad Lowe, who played Thomas Coville, the "villain of the week", in "The Faithful (2017)".
When Kara said I saw Clark do this once (spinning around and making a hole in concrete) is a reference to Superman (1978).
In the comics, Imra Ardeen is the member of the Legion of Superheroes known as Saturn Girl.
Mon-El says "grife", which in the comic books is an expletive used in the 31st Century by members of the Legion of Superheroes.
Mon-El mentions that the cure for his lead poisoning was developed by L-Corp, which suggests that Lena's desire to distance herself from Lex and do something good for the world has had some measure of success.