This episode did not air during Excel Saga's original run, because it was intentionally too violent and obscene for broadcast. It eventually aired in the UK on 25 March 2007.
This episode obliquely refers to the 1995 sarin gas attack on a Tokyo subway by including sarin attacks as a method of exterminating enemies.
Shin'ichi Watanabe in the Excel Saga DVD Volume 3 remarks that it "felt good to go past the limits of a TV series", although he thinks that "is not something that you should do too often".