The Mutation Situation - S2-E1
Trivia: At the very end of the episode, a squirrel drinks some mutigen and then suddenly looks back at the camera suddenly in a dramatic fashion. This is a reference to the" Dramatic Chipmunk" meme -the squirrel moves in the exact same way with similar music.
Trivia: When Barry and Oliver are fighting on the street, a police officer asks for backup and mentions Burton and Nolan street, as reference to Christopher Nolan and Tim Burton.
Trivia: Dio in this episode drinks Cronenberg Whisky, just like in the manga. The fictional brand is most likely a homage to the director David Cronenberg, especially given the bit of 'body horror' appearing in this arc.