Buffy The Vampire Slayer: 10 Funniest Episodes
11. Honorable Mention: Beer Bad (Season 4, Episode 5)
It would certainly be a shame to talk about the Scooby Gang's funniest outings without paying at least one modicum of lip service to its most objectively awful episode.
Beer Bad clearly has its heart in the right place by trying to tackle the murky world of freshman binge drinking in the show's signature snarky style, but everything about its execution is so completely over the top that you can't possibly take it seriously. The thrust of this episode is that an evil brewery is supplying the local college bar with a cursed beer that causes those who ingest it to revert to a lower state of being - i.e. they become cavemen.
A metaphor that's more content with punching you squarely in the nose than simply being on it.
As a result, your mileage with this one will vary between sheer bewildered at the offensively simple metaphor, or gleefully enjoying the campiest episode the show ever produced. If you're in the latter camp then Beer Bad is an absolute blast and its overt ridiculousness is its biggest strength.
For the rest of us though, it's simply funny for all the wrong reasons.