Corrected entry: At the end of Season 5, Buffy died. She was still dead into Season 6, before Willow raised her. Spike says she was dead 147 days. When one slayer dies, another takes her place (i.e., Kendra). The slayer's death does not have to be reported to anyone (example: the Council), as when Buffy died the first time and Xander gave her mouth-to-mouth to bring her back (she was only dead for a few minutes). A few episodes later - voila, Kendra. So, where was the new slayer after Buffy died at the end of Season 5?
Corrected entry: During season 1 it is mentioned a few times that if the Master rises the Hellmouth will open, since his being trapped in it has jammed it up. In 'The Wish' we see what Sunnydale would have been like if Buffy hadn't gone there and he had risen, so why didn't the Hellmouth open?
Correction: After Anya has made Cordelia's wish come true and all have entered an alternate dimension, there is no reason to believe that what was held true in one dimension also holds true in another. Therefore, it is perfectly acceptable for the Master to be footloose and fancy free in an alternate dimension, and never confined.
Corrected entry: If Angel presumably had an invition into Giles' apartment (to leave Jenny's body) why did he need to be reinvited again in "Amends"? Giles never had that un-invitation spell done, he doesn't have any herbs or crosses by his doorframe.
Corrected entry: In 'The Prom' Angel says he never drinks coffee. In season 2 we were told that (sometime between the episodes 'Reptile Boy' and 'Halloween') Angel and Buffy went out for coffee.
Correction: This doesn't necessarily mean that he drank any coffee - it's just a general expression.
Corrected entry: In the Season 7 episode 'Selfless' we are told that Anyanka was known as Aud back when she turned Olaf into a troll and had him imprisoned in the purple crystal, and that she only adopted the name Anyanka when D'Hoffryn made her a demon. But back in the Season 5 episode 'Triangle', when Olaf was released he refered to Aud as Anya straight away. He wouldn't have known about her name change.
Correction: First an error in the error. Aud/Anya did not trap Olaf in the crystal. Olaf says in Triangle "I adjusted. And then what happened? Witches. Filthy, dirty, disgusting witches. They trapped me. I was imprisoned in that crystal for centuries. Ohh, a curse on all witches. All must die." Aud turned Olaf in to a troll in 880, over a thousand years ago, and became Anyanka immediately after. Since Olaf had time to "adjust" to being a troll, it was most likely awhile before the witches entrapped him. Possibly even several hundred years. It is conceivable that in that time he ran into the new Anyanka or at least heard of what she was up to.
Corrected entry: In Series 7 Episode 14, it is indicated several times that Principal Wood is over 30 - Xander says he's 10 years older than Buffy, Wood refers to events 'back in his 20s', but Wood also says he was 4 when his mother died. In Season 5, the episode 'Fool For Love' we are told Nikki, his mother, died in 1980. This would make him only 26/27, not into his 30s.
Correction: Wood is actualy 30, both in Fool For Love and Lies My Parents Told Me the subtiles show the year 1977, not 1980.
Correction: Joss Whedon explained this one himself in an interview. He explained that when Buffy died the first time that triggered Kendra (and after Kendra died, this triggered Faith). Joss explained that the triggering ability only works once for each slayer so Buffy's second death would not call another slayer whereas Faith's death would.