Ace Combat 04: Shattered Skies is a 2001 combat flight simulation video game developed and published for the PlayStation 2 by Namco. The player assumes the role of a fighter pilot, assigned the call sign Mobius 1, and controls one of 21 different fighter jets through 18 different story missions. Each mission features different objectives including shooting down squadrons of enemy pilots and escorting friendly units.

Gameplay was given more of an arcade feel with an increased focus on score attack objectives and less story cutscenes. In addition to standard missiles that can lock on to any target, Ace Combat 04 introduced special weapons such as anti-ship missiles, unguided rockets, and bombs. Studio 4°C developed the interludes that play between missions as slide show cutscenes, which was a cost-effective alternative to the fully-animated cutscenes in Electrosphere. As opposed to the Top Gun-inspired rock music in Ace Combat 2 and the electronic music in Electrosphere, Ace Combat 04 features a blend of rock, orchestral, and synthesizer music, as well as a Latin chorus, which cemented the style of Ace Combat soundtracks going forward.