In flashback, an attorney gives Number 5 a Wolfram & Hart business card. If you look closely, on the bottom left hand side of the card, you can see the name of the lawyer, "Holland Manners, Associate Attorney." Holland Manners appears in the first season (decades after the events in this flashback) as a senior attorney at Wolfram & Hart.
Writer/director Jeffrey Bell explains that he always wanted to work Mexican wrestling into one of his The X-Files (1993) scripts, but it wasn't until he pitched the idea to Joss Whedon that he was able to realize his "lifelong dream - to tell a story about Mexican wrestlers."
When Angel mentions "The Father Will Kill The Son"-prophecy, Wesley says "What are you talking about?". Wesley doesn't remember anything about that prophecy (despite it being the cause of his betrayal of Angel in Season 3) because of Angel's "deal" with Wolfram & Hart (in Home (2003)) in which Angel agreed to take over the Los Angeles Branch in exchange for Connor being given a new (normal) family and home. This causes everyone (except Angel, Eve, Cordelia, and Cyrus Vail) to forget all about Connor (including the prophecy).
When Carlos is attacked at the start of the episode, as he is thrown through the air, he emits the infamous Wilhelm scream. This familiar scream sound effect has been heard in over 140 movies and various TV shows.
The speech Angel gives to Número Cinco at the wrestling match is a re-wording of the "If Nothing We Do Matters" speech he gave to Kate in Epiphany (2001).