Other mistake: In the famous scene where Buffy tells Giles, "If the Apocalypse comes, beep me," she grabs her pager from out of shot. Trouble is, she's standing in the middle of her hall and there's nowhere she could have picked the gadget up from. (00:21:00)
Other mistake: In the episode 'Anne' Kenn tells Buffy that time in his hell dimension passes more quickly, that one day on Earth is the same as 100 years in his dimension. This means time goes roughly 36,000 times quicker. When Lily falls into the portal, it's at least 10 seconds until Buffy jumps in after her, but Lily is still just sitting there looking stunned. If times moves that much faster, 10 seconds would become over 4 days. Would Lily still have been just sitting there?
Other mistake: When Angel, Drusilla and The Judge enter the mall, The Judge kills a pedestrian as he tries to get away. But no other pedestrians that are in the mall notice - A big blue guy just set a man on fire and disintegrated him into tiny pieces in a public mall and NOBODY noticed?
Other mistake: Just after Giles becomes completely blind, Spike gets up to get a book off of the mantle. When he does this you can, very briefly, see James Marsters reflected in the glass doors of the bookcase that was behind him, despite Spike being a vampire. (00:27:00)
Other mistake: In all episodes where the high school football team is mentioned, they are called the RAZORBACKS but in this episode the cheerleaders cheer for the GREENBACKS (it wouldn't even make sense if this was a nickname as SHS colours are yellow and burgandy).
Other mistake: Joyce tells Cordelia to grab some bandages for Xander from the bathroom upstairs. Joyce and Xander are in the kitchen and there is a small corridor that leads to the stairs, but Cordelia goes around the other way leading to the living room. Fair enough, Cordelia made a mistake. She isn't that bright. But she returns with the bandages coming back from the living room. Why come downstairs and then go All The Way around through the living room when she could have just walked down the small corridor?
Other mistake: When The First (disguised as Eve) tells the Turok-Han to kill everybody except Buffy, it runs past her towards the exit of the crypt. The First then says, "Well, alone again", turns to face Spike and transforms into Buffy. In this shot, the Turok-Han can be seen still leaving the crypt, even though it had plenty of time to reach the exit and was running towards it at full speed.
Other mistake: In the final scene, where Spike drives down the road while singing 'My Way' he turns the steering wheel significantly, but in the external shots the car is travelling down a straight road, with no bends. He is turning it sharply to the right as the camera cuts to outside, but the car continues straight ahead.