There are various references to the movie 300 in this episode. The over the top slow motion style is used many times in the film as it is here. The Persian leader is called Xerxes and is outrageously tall and has multiple facial piercings, just like the movie version. Also, Xerxes sits on top of a golden hummer, rather than the temple-like platform from the movie.
Also the film is narrated, as is this episode and the number of lesbians fighting the Persians is 30, one digit off of 300.
An example is:
Persian:This is crazy!
Ms.Garrison: This isn't crazy, THIS IS LES BOS!
(Kicks Persian's nuts, falls in slow-mo)