Diggle's extreme susceptibility to motion sickness is once again witnessed, with Caitlin and Cisco preparing a trash can for his inevitable bout of vomiting following Barry superspeeding him into S.T.A.R. Labs.
Cisco likens DeVoe to the Legion of Doom, suggesting they send the "Super Friends" to defeat him. The "Super Friends" typically refers to the Justice League of America, the name originating from the TV series of the same name. In that series, the Legion of Doom were also an enemy of the Super Friends.
When Cisco is looking at the specs for the Argus facility, he uses the phrase "Frell me." That term was widely used on the TV series Farscape.
When the delivery guy delivers Joe and Cecille's food, he goes to compliment the house. Joe suggests the phrase "bitchin'", a callback to the season premiere in which the team decodes a message from an entranced Barry that seemingly says "this house is bitchin'".
Barry says he checked Black-Hawk Island, in the comics Black-Hawk Island is Hawkman's hide out and is the base of a an international team of heroic WWII pilots called the Blackhawks.