The development cycles of video games spreads longer than most people care to imagine. Some take a few quick years while others take the better part of several decades. But each one shares one common quality that is unto itself a monumental achievement: the creation and completion of a musical score. Like the game they are implemented in, some are easily put together faster than others due to what it comprises of while others take a gigantic amount of effort and patience to pull off. Video game soundtracks from way back when (i.e. Super Mario Bros. and Galaga) represented the best of the best when it came to computer sounds and the use of soundboards and simple effects. In this day and age, things have taken a huge leap into the complex: full scale orchestras, a technical boost is computer effects and digital composition, and the power to combine the two together for one massive package. The Halo series is exactly that when considering how far the series has come since its November 2001 inception into the media. Not only did it provide a provocative, exhilarating campaign, but one of the most memorable video game soundtracks since Perfect Dark or Super Mario Bros. As the series expanded and became a multi-selling, platinum-defining hit, the need to carry on its musical legacy continued, and with each game released there was always something audibly appealing to hear. The first Halo built the base, while Halo 2, Halo 3, ODST, Halo Wars, Reach, and Halo 4 created the monstrous foundation for which it stands on today. And come 2014, when Halo 5 is released, that foundation will only increase in size and complexion. This newly inspired list contains 25 of the most memorable, captivating, invigorating musical tracks from the Halo universe from the minds of those who brought their imaginations together to form a strong stimulating audio package that stands among the giants of the industry. Note: None of the original Halo themes are in this list, as it would be a little too obvious if one of them made an appearance here in a list which shows off the fullest extent of the series' talent. Also, none of the remixed tracks from Halo: Combat Anniversary appear, nor does any of Halo: Reach's audio appear. There will be a few major spoilers further down the road, giving away key events for some of the games, so if you have any interest in playing through the campaigns without knowing any of the surprises, you might want to skip through the track descriptions. Now, let the countdown begin: