"Magnificent" originated from the band's improvised recording sessions with Brian Eno and Daniel Lanois in Fez, Morocco in June 2007.

"[4] The song has been remixed numerous times, including versions by Dave Audé, Pete Tong, Redanka, Fred Falke, and Adam K & Soha.

[8] The synthesized baseline of Redanka's 180 Version Remix is similar to Donna Summer's 1977 hit song "I Feel Love".

'"[1][13][14] In Allmusic's review of the album, Stephen Thomas Erlewine said that on "Magnificent", U2 "strike that unmistakable blend of soaring, widescreen sonics and unflinching openhearted emotion that's been their trademark, turning the intimate into something hauntingly universal".

[15] Mojo praised the song, noting the song's "martial snare drums ratchet the Edge's vertiginous delayed guitar figures across a rock landscape that this band realised to near perfection c. The Unforgettable Fire and which they've now updated with no loss of awe".

[16] Blender called the song a "rocker" and "yet another hymn to the powers of love" in which the band "achieve liftoff".

[17] NME was critical of the song, calling it "astonishingly uninteresting", adding that it "sounds like [it was] reconstituted from the ...Atomic Bomb sessions".

The song also made a one-week appearance on the Billboard Hot 100 upon No Line on the Horizon's release, peaking at number 79.

Coldplay have regularly played the song prior to the band taking the stage at their concerts on the Viva la Vida Tour.

[1] "Magnificent" was debuted on the promotional tour for No Line on the Horizon, being played on the BBC Rooftop, on the Late Show with David Letterman, and at a mini-concert at Fordham University taped for Good Morning America.