Super Smash Bros./Awesome Music

"Audi famam illius. (Hear the fame of that one!) Solus in hostes ruit (Alone he rushed into his enemies) et patriam servavit. (and saved his country.) Audi famam illius. (Hear the fame of that one!) Cucurrit quaeque (He ran,) tetigit destruens. (destroying everything he touched.) Audi famam illius. (Hear the fame of that one!) Audi famam illius. (Hear the fame of that one!) Spes omnibus, (Hope to everyone,) mihi quoque. (also to me.) Terror omnibus, mihi quoque. (Fear to everyone, also to me.) Ille (That one) iuxta me. (is near to me.) Ille iuxta me. (That one is near to me!) Socii sunt mihi. (They are allies to me,) qui olim viri fortes rivalesque erant. (Those who were once strong men and rivals.) Saeve certando pugnandoque (And by contesting and by fighting fiercely) splendor crescit. (Surely our splendor grows.)"

- The Super Smash Bros. Brawl main theme

In addition to its own music, the Super Smash Bros. series has a habit of taking older music tracks and making them awesome, whether they already were or not. The entirety of Brawl's soundtrack alone could count considering it featured the largest number of videogame composers to work together on a single game.

Note: If the music is unchanged from its original game, then put it in its relevant section of Crowning Music of Awesome, not here.

Original

 * Both Multiman Melee battle themes (remixes of the opening theme) are pretty awesome.
 * Super Smash Bros. Brawl: The main theme, complete with Latin chanting and translation, heard in the intro movie and after beating the Subspace Emissary. Being from Nobuo Uematsu, how it couldn't be awesome?
 * The new Final Destination, which is the main theme combined with BLAZING ELECTRIC GUITARS.
 * Also, Battlefield, the main theme remixed for large scale battles and Crowning Moments of Awesome.
 * The Boss music from Subspace Emissary is pretty awesome in its own right.
 * Tabuu's Theme is (one of) the best original songs from Brawl, and it isn't (entirely) a remix of the main theme!
 * From the first Smash: Meta Crystal (Metal Mario Battle).
 * Melee's Metal Battle made a pretty good fight too.
 * The credits music from the first game is very enjoyable. It even got a remix in Brawl!
 * SSBB's credits theme is a medley of the previous two games' credits themes and is a fitting end to an epic story mode.
 * Melee has two awesome menu themes. And an awesome opening theme.
 * The Battlefield version.
 * The target test track from Melee. Watch the comments on pretty much any Youtube video with that song. You get at least ten people complaining about how that song isn't in Brawl. Considering how awesome it sounds, that's understandable.
 * The original game's theme was reworked into Final Destination for Melee.
 * Is the ominous song played for Cruel Brawl awesome? Some would say yes. Can you hear it outside of Sound Test without pausing in Cruel Brawl Mode? NO, Gosh Darn It!
 * The "How To Play" music of Melee/Brawl qualifies as another awesome Wasted Song, as the player cannot hear it in Brawl's Sound Test.

Animal Crossing

 * Go K.K. Rider! is high on many a player's favorites list.
 * The 2:00 AM remix in Brawl is a neat rock/pop remake of what was originally a very low-key, mellow jazzy piece.
 * Even if not very fit for fighting, the double remix of Tom Nook's Store and Town Hall is so catchy enough to make you come back to listening it. And if you don't, you're gonna whistle it on forever.
 * The Roost/Brewster's Roost is a beatiful arrangement of the original which sounds like from a romantic movie.
 * Title (Animal Crossing: Wild World) rains gentle chills of nostalgia down to your spine, reminding you of those times of playing Animal Crossing on DS so addictively. Sucha cheerful tune.
 * And for more dedicated Animal Crossing-players, the composers hid in some recognisable tunes from the series in the tune:
 * Blather's Museum-Theme can be heard (topped with clock sounds)
 * There are throwbacks to 3pm-4pm's and 6am-7am's-tunes (which would play each corresponding to the real-life clock in your DS.)
 * And most of all, the Loan Paid Off-jingle is also included, just for the hard workers who spend their months (or maybe days) paying their loan for Nook in order to get a bigger house. How dedicated!

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 * The Jungle music from Donkey Kong tends to get overused somewhat, but there's no denying that each version is very good in its own right.
 * Melee's Donkey Kong Rap remix takes one of the Guilty Pleasures of Donkey Kong 64 and makes it even cheesier, if that's somehow possible.
 * Brawl also has King K. Rool's Boss theme from the original DKC (contrary to the name of the song and the sudden change in tone, it's actually one track, not two), and Bramble Blast/Stickerbrush Symphony from Diddy's Kong Quest, often considered one of the best tracks in Brawl (as well as from its original game).

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 * Along the same lines of the Brawl opening/ending, the popular Fire Emblem Main Theme was given the full Latin Opera treatment. Also there's the character encounter (known as "Together we Ride" in FE7) theme remixed from Melee.
 * There's also the incredibly catchy Attack, from the seventh game, and the Shadow Dragon Medley, from the original.
 * With Mila's Divine Protection.

F-Zero

 * Melee's rocked out version of Mute City.
 * Brawl's is a little closer to the original.
 * Fire Field, 2 minutes and 18 seconds of pure, concentrated epic guitar.
 * White Land.
 * Big Blue. No more needs to be said.

Kid Icarus

 * A newcomer to Brawl, Kid Icarus brings us gems like Underworld and the Title Music.
 * Nostalgia points for cleverly arranging Reaper's Theme to switch right into the Game Over Theme in Underworld-remix right before the music would be looped back to beginning, as to remind the longtime/hardcore Kid Icarus-fans of how responsible the Reapers were for Pit's countless amount of deaths and making him start all over again at the beginning of the stage.
 * Skyworld is also very majestic and adventurous rendition of the Overworld/World 2-theme from Kid Icarus, reimagining about the heroic sidescroller part on land after the painful beginning that is Underworld.

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 * While Gourmet Race is often the track used for Kirby in Smash, the closest thing to a main theme the series has is Green Greens.
 * Gourmet Race. As a thrasher-metal song. Several commenters mention that Kirby must've swallowed Guitar Hero at some point.
 * Fountain of Dreams' music, which is essentially a orchestrated "Gourmet Race" remix.
 * The Smashing! Live! version is pretty good too.
 * The reworking of the final battle music in Kirby Super Star.
 * Also: Meta Knight's Revenge.
 * And again, King Dedede's Theme was converted from 8-bit right up to an orchestra piece. Arranged by YOKO GODDAMN SHIMOMURA.
 * More love for Kirby: Butter Building is just so unrelentingly happy.
 * Have you noticed that in that theme they used electronic accordion and bongos to emulate the feel of the NES soundbits from Kirby's Adventure tracks anyway? Try to listen for this for an example. You need to have very good ears for to hear the bongos similar to the remix, though.
 * It's the Title Theme from the first Kirby game!!! They didn't forget about Kirby's Dreamland after all!!
 * Squeak Squad Theme is a needlessly underrated track.
 * Every hardcore Kirby-fans will easily love Boss Theme Medley, which takes all the best tunes throughout Kirby's history of battles and throws it into awesome medley fest. Particularly the first four (Adventure, Dreamland 2, Super Star and Kirby 64) is sure to give goosebumps of Kirby-gaming nostalgia.
 * "The Legendary Air Ride Machine". Holy crap.
 * The incredibly calm and peaceful All-Star Rest Area from Melee, which is originally from Super Star, which is itself based off Float Islands from Kirby's Dream Land.

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 * One cannot mention Zelda without mentioning the Main Theme.
 * Or, if you prefer: the Main Theme.
 * And for those who like their choices, the Main Theme.
 * The original Legend of Zelda overworld/dungeon. Brawl version. Ominous Latin Chanting and Ominous Pipe Organ together in one amazing song.
 * Tal Tal Heights, which is actually a mix of the Link's Awakening overworld and the actual theme of the same name, is possibly the best of the many overworld Zelda remixes.
 * Ocarina of Time Medley, a mix of the six main tunes Link can play on his Ocarina, is pure nostaliga for Ocarina of Time in song form. Melee also had Saria's Song by itself, which unfortunately wasn't retained for Brawl.
 * Song of Storms. An amazingly epic remix of Windmill, Ganondorf's Theme, and the Serenade of Water. If anything, the first 3-4 seconds of the song, that INTRO, should tell you the epic you're in for.
 * Either of Hyrule Temple's tracks.

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 * The SSBB version of Metal Gear Solid 4's Theme of Love.
 * Also Encounter, the, um, encounter theme from the first MGS.
 * The Brawl version of Theme Of Tara from Metal Gear.

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 * The Main Theme(Brinstar). Melee's version is huge fan favorite. Brawl's would be too, if not for the voice at the start.
 * Vs Ridley is nothing short of raw, unmitigated badassery in musical form.
 * The remastering of the original Metroid's ending theme. Especially epic because it plays when you beat the final boss in Classic or Boss Battle mode as Samus. Delicious chills shooting straight into your soul, man.
 * Melee's version of Brinstar Depths is just amazing. Especially when the melody hits the second repeat and the drum track kicks in.
 * the Theme of Samus Aran, SPACE WARRIOR. Bonus points for playing the part of Theme Music Power-Up during "The Subspace Emissary" when Samus gets her power suit back.

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 * What about the theme for the Melee level of Onett from Earthbound? The alternate song, "Pollyanna (I Believe In You)", is great. There aren't even any vocals in there, but you want to sing along anyway.
 * Melee had the theme for Fourside, which is also notable for being the only track that originates from Earthbound/Mother 2, rather than Mother 1 or 3. For some reason, this theme not only didn't return for Brawl, but a handful of Earthbound tunes were considered for Brawl but not put in!
 * At least the second half of Earthbound's Eight Melodies has endured as Ness's victory fanfare - oh, wait, no, he and Lucas share a victory theme taken from Mother 1 in Brawl. More of a Wall Banger when you realize that Meta Knight has his own unique variation of the Kirby victory theme play when he wins.
 * Humoresque of a Little Dog, AKA the shop theme. A little out-of-place for a heated free-for-all, but awesome nonetheless.
 * Brawl also gives us the haunting-yet-pretty remix of "Snowman" from the original Mother (Earthbound Zero) and "Unfounded Revenge/Smashing Song of Praise" from Mother 3.

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 * Victory Road is an total fanservicey rock approach to the ones who were introduced to PKMN at middle 2000's rather than ending 90's.
 * Route 209.
 * Team Galactic Battle.
 * Road to Viridian City (no relation to the anime's song) Remix. That is all.
 * Dialga/Palkia Battle At Spear Pillar!. Holy crap.
 * Heck, even the Pokémon Center gets an epic remix.
 * The best wild Pokémon battle themes of the series, those of Sinnoh and Johto, both recieved insanely EPIC remixes in Brawl and Melee respectively. Both are in Brawl.
 * Observe, Wild Pokémon Battle (Diamond/Pearl), and Johto's "Battle Theme" medley!
 * Not to be outdone, the Wild Pokémon battle music from Hoenn also got an amazing remix. Listen and bask in epicness!
 * Or if you've got your Nostalgia Filter on, you could just stick with the Kanto battle theme medley that played on Melee's Poké Floats stage.
 * Not to mention the Pokémon Gym/Evolution medley music. Listen and tell me this isn't awesome.

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 * The Angel Island Zone Remix. Such a pity that it was the only Sonic song that got a remix for Brawl...
 * The instrumental version of His World is nice to listen to while fighting, mainly since there aren't any distracting vocals to put you off.

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 * First off, they have both Main Themes from the SNES and N64 games.
 * Corneria has always been a fan favourite, though it took until Brawl to get a remix of it.
 * And of course, Star Wolf.
 * Area 6

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 * Of course, there's always the most famous video game theme of all time. Koji Kondo himself made this remix of the Super Mario Bros. Ground Theme.
 * The Underwater Theme, which takes a classic, and gives it two remixes along with the original all in one track!
 * Title/Ending (Super Mario World) is a tearjerkingly happy overture for ones who owned Super Mario World as their first Mario-game, composed of catchy beginning, and is carried onto bittersweetingly composed fast-tempoed ending theme.
 * Mario Kart DS has the already kickass Waluigi Pinball. The Brawl remix gives it a techno-speedup overhaul, along with mixing in themes that would later be used in Wario Land: Shake It.
 * Luigi's Mansion is given a perfectly fitting haunting track for its stage.
 * For most surprising Mario tune in Brawl we have the Easton Kingdom theme from Super Mario Land.
 * Main Theme (New Super Mario Bros) is very catchy to listen, and if that wasn't enough, the Stage Clear Theme at the end of the theme makes it more worthwhile for NSMB-players.
 * Melee's Dr. Mario!
 * And if you are more of a fan of Chill than Fever, Brawl has this for you!
 * Princess Peach's Castle. The best way to kick off Melee's Adventure Mode.
 * Rainbow Cruise.
 * To round off our Melee songs, we have Super Mario Bros. 3.
 * Gritzy Desert from Mario & Luigi: Partners In Time. It's like Lawrence of Arabia with techno!
 * The Air Ship theme, really gives off a creepy vibe of the Doom Ship coming to abduct you!

Wario Ware

 * Wario Ware gives us three Ear Worms in the forms of Ashley's Song, Mona Pizza, and Mike's Song
 * If you're one of those people who can't stand English lyrics for some reason, there's also the Japanese versions: Ashley, Mona, and Mike.
 * There's Wario Ware, Inc. the menu screen from the first game, and Wario Ware, Inc. Medley, a hilarious medley of sound clips from various microgames and features also from the first game

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 * The Brawl version of Flower Garden of Yoshi's Island.
 * The mix of Obstacle Course, which changes into this version over time.
 * The Wilderness theme from Yoshi's Island DS is terrific too.
 * The Brawl remix of the Yoshi's Story Ending Theme.

Misc.

 * Shin Onigashima. Really, if the original song would have qualified (several more are cited below under their original games), it got put into Brawl and made even more awesome.
 * Lip's Theme of Panel De Pon-fame is very technoish and catchy rendition of the original, with more clapping and beat than ever before.
 * Is the technoish style of the song maybe a throwback to the soundtracks of the latest Panel De Pon-game back then, Planet Puzzle League?
 * If you ever wondered how to make Tetris music more awesome, Yoko Shimomura did it with Type A
 * Ever wonder how a Mariachi remix of Tetris tune might sound? Well, now you know.
 * There's only one Golden Sun track, but it's possibly one of the most epic battles themes ever.
 * Clu Clu Land is just addictive.
 * When you finish a great match, you know you love to hear your favorite character's arranged victory theme. Especially if you know where it came from, and can reminisce about how great it felt to win back in the day too.
 * Shaberu! DS Cooking Navi might be the most unknown theme of all in whole Brawl's library, from a electronic cookbook application for DS, released only in Japan (back then) but you can't help but admit it's also the one of most magical tracks in the game.
 * Ice Climber.
 * They can even make epic tunes from sound effects, as shown from Flat Zone 2 and PictoChat.
 * The first Flat Zone Theme.
 * Pikmin has an absurdly underrated soundtrack, so it's awesome to hear two great remixes of its music in Brawl with Pikmin 2's World Map theme and Stage Clear/Night Comes.
 * Brawl's remix of Balloon Trip just makes you want to get up and dance.
 * X Tunnel Scene from Brawl again. A little-known shooter game from the Game Boy gets a kickass techno remix.
 * Gyromite is a great song, especially for R.O.B.
 * The orchestral live album Smashing...Live! is chock full of fantastic arrangements of melodies from Melee. One such piece is the "Smash Bros. Great Medley," especially the Big Blue section.

Remixes

 * Even the weapons aren't immune. Think the hammer's music is unworthy of a remix? Let me prove you wrong. Bonus points for the hammer pulling a Superman pose.
 * Three words: Mario, Wario, Lucario.

Other

 * The guys at Balanced Brawl chose a really fitting soundtrack to showcase the improved cast with.