- Not to be confused with its precursor Back to Saturn X: Episode 1
Back to Saturn X: Episode 2, abbreviated in-game as BTSX: Episode 2, informally known as BTSX 2, sometimes elongated to Back to Saturn X: Episode 2: "Big Towers," Says Xaser or Back to Saturn X: Episode 2: Tower in the Fountain of Sparks and possibly incorrectly referred to as BTSX or Back to Saturn X is a mod for DooM II devolved by BTSX Team and released on September 1st, 2014. It is a sequel to Back to Saturn X: Episode 1 with the same graphical changes as the last, but with a brand new soundtrack. Although not officially devolped, licesened, or published by id Software, it is officially supported by them, as it was released as a free add-on for 2019 remasters of The Ultimate DooM and DooM II/The Master Levels, alongside its precursor Back to Saturn X: Episode 1, on June 26th, 2020. It has a planned sequel named Back to Saturn X: Episode 3.