Other mistake: Just before the evil robots capture Bill and Ted's girlfriends, after they crash through the window, the girlfriends ask the robots: "Who are you?" and Bill goes "Well, I'm really Evil Ted!" and unzips himself and out pops Evil Ted, and the other robot goes, "And I'm really Evil Bill!" and out pops Evil Bill. When the robots are herding the girlfriends out just before knocking them out with their breath, you can see two sets of clothes in the bottom left corner if you watch closely.
Continuity mistake: In the scene where Death and Bill are playing Twister, Bill's left hand was on red and his right hand was on green. In the next shot when Death is putting his foot on blue, Bills hands are switched.In the same scene Bill's shoes are on the floor. After he wins they walk over to Death and his shoes are back on. He never had time between all the dialog to put them on.
Trivia: Much of the guitar work done in this film was by guitar hero Steve Vai, who also worked on PCU and, perhaps more famously amongst guitarists, Crossroads. Pretty much all the guitar licks which are played throughout the film when Bill & Ted play air guitar are played by Steve, as well as "The Reaper Rap" - in the end credits.Sam Johnson
Ted: You are a most excellent scientist, Station.
Bill: Yeah! Plus, you got an excellently huge Martian butt!
Big Station: Station!
[Dead Bill S. Preston almost falls down when climbing around in Hell.]
Dead Bill: Ted.
Dead Ted: Yeah?
Dead Bill: If I die, you can have my Megadeth collection.
Dead Ted: But, dude, we're already dead.
Dead Bill: Oh. Well then they're yours, dude.
Grim Reaper: A hit. You have sunk my battleship!
Question: When the titles are running at the end, just after the headlines have stopped, the screen goes to black and the first title you see is "Taj Mahal". Obviously, I know what the Taj Mahal is, but why is it mentioned in the titles?