While fighting Bishop, Sara remarks that "destiny is so last season," referring to how the Legends faced the threat of the Loom of Fate. This also references the fact that the original Sara Lance was revealed to be the Paragon of Destiny.
John Constantine's demons manifested by the blood vial's withdrawal symptoms are a possible reference to Demon Constantine. John's dark mirror infused with Aleister Crowley from Hellblazer.
Bishop reveals he has transferred his consciousness from clone to clone over 200 times, meaning he may have lived for centuries. The first main antagonist of the first season, Vandal Savage, was a similarly long-lived and manipulative villain who believed his methods would save humanity and also had long hair and a beard.
As with Bored on Board Onboard (2021), this episode mostly takes place on the Waverider with a few scenes taking place in Constantine's house.
Bishop uses the word "kib-BITZ." The word is actually pronounced "KIB-bitz," usually "kibbitzing." It's a Yiddish word meaning chatting or kidding around, an easy mistake to make if the actor has only seen the word written but never heard it.