Psycho Demon

The following lines were deleted from the episode Entropy:

and

Shopping girls

Buffy and Dawn go shopping in Entropy, as Buffy tries to make up for Dawn for nearly killing her. The scene was filmed on the Santa Monica promenade in L.A. It’s near Venice Beach.

Spike ‘n’ Anya

Marti Noxon said about the episode Entropy: “The Spike-Anya thing really worked. Those two characters have a real chemistry together and it’s fun to say, ‘Oh, that works.’ Also we were just trying to put the knife in a little bit deeper.”

Kali Rocha

Kali Rocha played Spike’s crush Cecily when he was a human, and later went on to play vengeance demon Halfrek. Kali has appeared in Gods and Generals, White Oleander, Meet the Parents, The Object of My Affection, The Crucible, Will & Grace and Becker.

Halfrek

Halfrek was a vengeance demon who specialised in vengeance for abandoned children. Halfrek was both a friend and rival of Anya. She was cynical of Anya’s relationship with Xander. Halfrek tricked Dawn into making a wish which locked the Scoobies in Buffy’s house during a party, as she realised Dawn was very lonely. Halfrek was killed by D’Hoffryn as revenge for Anya’s decision to become human.

Beady eyes

In Once More, With Feeling, Anya sings about Xander, “His eyes are beady!” to which Xander later replies, “…and my eyes are not beady!” Even later in the episode, Anya sings, “Beady Eyes is right! We’re needed.” In the episode Entropy, Anya is trying to wish revenge on Xander, and she says, “I wish you had tentacles where your beady eyes should be!”

Comforting

In the season four episode Where the Wild Things Are, Spike and Anya talked about getting revenge on Drusilla and Xander. They also bonded over the loss of their respective powers. They abandoned the ‘revenge’ idea and instead Anya took Spike to a party. Spike “comforted” Anya again in Entropy after her break-up with Xander. They mention the event again in Sleeper and Get It Done.

Same Graveyard

The cemetery which Callie runs through at the beginning of Reptile Boy is the same one used in the season six episode Entropy where the nerds ride their ATVs, chasing a vampire. The graveyard features tombstones reading “Mother” and “Dad”. Nice and vague.

Willow’s dress

When Tara is talking to Willow at the end of the episode Entropy, Willow’s dress from Once More, With Feeling can be seen hanging on the door.

Xander’s jealousy

Xander’s old feelings for Buffy come out in the episode Entropy, when he discovers that Buffy has been sleeping with Spike. His feelings for the Slayer haven’t been mentioned for a while, but he was obsessed with her in the first couple of seasons.

Alison Krauss

In When She Was Badm we hear Alison Krauss & Union Station’s ‘It Doesn’t Matter’ as Angel leaves Buffy’s bedroom (from the albums So Long, So Wrong, and Buffy The Album). In Entropy, we hear ‘That Kind of Love’ by Alison Krauss, after everyone argues about Spike and Anya.

Tom McRae

In Entropy, a depressed Xander listens to ‘Sao Paulo Rain’ by Tom McRae. Xander was last seen indulging in a teenage moody session to music in Prophecy Girl.

No vengeance for demons

Anya returns to Sunnydale in Entropy as a vengeance demon. Halfrek reminds her that vengeance demons are unable to seek vengeance for themselves.

Babylon 5

Babylon 5 has been referenced a couple of times in Buffy. In The Replacement, Xander mentions his Babylon 5 commemorative plates. In Entropy, we learn that Jonathan used to collect Babylon 5 novels. Danny Strong, who played Jonathan, attended a Buffy Convention in London in 2003, alongside Babylon 5 star Julie Caitlin Brown.
Robin Sachs (Ethan Rayne) played Hedronn in the show and Robin Atkin Downes (Machida) played Byron, a poetic telepath, in Babylon 5.

Chippewa Bay, NY

In Entropy, when Willow is talking to Tara about going for coffee, she is wearing a red t.shirt with the name of a town on it - Chippewa Bay, NY. This is a tiny summer resort town on the St Lawrence River in upstate New York. The total population year round of the town would be less than 200.

Indiana Jones

Warren calls Jonathan “Short Round” in Conversations with Dead People and Entropy. He was Indiana Jones’ partner, played by Jonathan Ke Quan, in Indiana Jones and the Temple of Doom. In All the Way, Zach says to Janice, “Pumpkins, very dangerous, you go first”. This is a reference to Raiders of the Lost Ark in which Indiana Jones sees snakes in his way. His friend Salla says “Asps, very dangerous, you go first”.
In Awakening, Angel says, “Wood. Why did it have to be wood?” after he sets off the booby trap. This is a paraphrase of Indiana Jones’s famous line “Snakes. Why did it have to be snakes?” from the 1981 film Raiders of the Lost Ark. Much of the action in Angel’s fantasy in Awakening is inspired by Indiana Jones movies. In Soulless, Angelus says to Wesley, “Here’s one for you. What’s the deal with Angel and Raiders of the Lost Ark?”

International House of Pancakes

Dawn makes a comment to Buffy in Entropy about her huge breakfast, “Are we going international?” This is a reference to a chain of restaurants called the International House of Pancakes. They sell massive breakfasts. IHOP are not as international as they’d like to be: they only have branches in the U.S. and Canada.

Star Wars

George Lucas’s Star Wars films are a cult phenomenon. They are referenced numerous times in the Buffyverse. The original trilogy included the movies Star Wars (1977), The Empire Strikes Back (1980) and Return Of The Jedi (1983) and the movies The Phantom Menace (1999), Attack of the Clones (2002) and Revenge of the Sith (2005) were made later on.

• In When She Was Bad, when Xander and Willow play Guess the Movie from the tag line (Willow: “Use the Force, Luke.”,
  Xander: “Do I even have to dignify that with a guess?”)
• In School Hard, Spike told Angel that, “You were my Yoda!” Yoda was the ancient Jedi master who became the mentor and teacher for both Obi-Wan Kenobi and Luke Skywalker.
• A visual reference to Star Wars can be seen in The Zeppo, when Xander runs into the corridor and runs back out with the gang members chasing him. Han Solo does the same thing in Star Wars.
• In Choices, Buffy says that Faith has turned to ‘the dark side’.
• In The Freshman, Xander confuses the Star Wars Jedi code quoted by Yoda in The Phantom Menace. (”Hate leads to anger…no wait…Fear leads to hate, hate leads to the dark side”). Also in that episode, the old frat house that the vampires are holed up in is the Psi Theta house. If you write those two greek letters together, and pronounce them together, you get Sith.
• In Fear, Itself, Xander says to Oz, “Sensing a disturbance in the Force, Master?”
• Buffy using the chain to choke Sobek the snake-demon in Shadow is reminiscent of Princess Leia killing Jabba the Hutt in Return of the Jedi.
• In Forever, Ben calls Glory’s minions “Jawa rejects” after the small hooded and robed creatures in Star Wars.
• In Life Serial, Andrew paints a Death Star from Star Wars on the side of the gang’s van. It’s the Empire’s revised design from Return of the Jedi, which Jonathan says is flawed.
• In the episode Two To Go, Andrew says, “We’ve got maybe seconds before Darth Rosenberg grinds us all into to Jawa burgers and not one of you bunch has the Midichlorians to stop her.” These are all Star Wars references: Darth is a title given to a Sith Warrior (such as Darth Vader); Jawas are the hooded creatures who live on Tatooine, and Midichlorians are micro-organisms which exist in all living things. Andrew says, “Laugh it up, Fuzzball” which is a quote from Star Wars. Andrew also later says in Two To Go, “…in a galaxy far, far away” - yet another Star Wars reference.
• In All the Way, Tara and Willow see a couple dressed as Princess Leia and Luke Skywalker kissing in the Bronze. Willow asks, “Do they know they’re brother and sister?”
• In Smashed, we see that the three nerds own a mint condition (though out of its packaging) 1979 Boba Fett action figure. Though Boba Fett was first introduced in The Empire Strikes Back (made in 1980), the earliest Boba Fett figure was made in 1979, before the film was released.
• In Dead Things, Jonathan and Andrew play fight with green light sabres.
• In Entropy, Warren calls Jonathan “Padawan”.
• In Conversations with Dead People, Jonathan and Warren have the following conversation: Warren: “Come on, “If you strike me down…” Andrew: “I shall become more powerful than you could possibly imagine…That boy is our last hope.” Warren: “No, there is another.” These are all quotes from Star Wars.
• In Potential, Xander says to Andrew, “Say Skywalker, and I smack you.” He is, of course, referring to Star Wars‘ Luke Skywalker.
• In Showtime, Andrew says, “I’m bored. Episode I bored.” He’s referring to George Lucas’s disappointing movie Star Wars Episode I: The Phantom Menace.
• In Never Leave Me, Warren/The First says, “I’m like Obi Wan”. He also says to Andrew, “We’re right in the trench, and the exhaust port’s in sight.” This is a reference to the scene in Star Wars in which the Death Star is under attack.
• In Bring on the Night, Andrew says, “I’m like Vader in the last 5 minutes of Jedi with redemptive powers minus a redemptive struggle of epic redemption which chronicles…” He’s referring to the last scenes of the final Star Wars movie Return of the Jedi.
• In Storyteller, there are two framed Star Wars comics on the wall in Andrew’s opening scene.
• In Dirty Girls, Andrew says, “But like so many tragic heroes, Faith was seduced by the lure of the dark side.”

Thermodynamics

Entropy (the title of a season six episode) is the second law of thermodynamics. It basically means that the more you try to put things together, the more they fall apart.

Seen at 14.33 minutes:

Buffy puts pancakes on a plate for Dawn, then the two discuss Dawn patrolling with Buffy. Then at 16:15 we see that the pancakes have disappeared, without Dawn eating them.

Seen at 16.47 minutes:

Anya is trying to get the Scoobies to make a wish against Xander but in some scenes she’s not wearing her vengeance demon necklace. She can’t make a wish without it. She is sometimes wearing the necklace underneath her red top, and sometimes not.