This series takes lots of inspiration from mecha animes such as GaoGaiGar, and as such it brings loads of hot blooded music to the table with it! To begin with, "We Are Xros Heart" by the magnificent Kouji Wada continues the Digimon tradition of seriously kick-ass evolution themes. Also dubbed "the ending theme" by fans, since the show has no real ending credits, and this song has a tendency to show up at the end of the episodes, usually during Moments of Awesome. The DigiXros-theme, which tends to play immediately before "We Are Xros Heart", is cool too.
Kiriha gets his own theme music as well, complete with lyrics that describe his blazing blue flames perfectly, Blazing Blue Flare. Makes any moment of the series where he's kicking ass all the more awesome, usually always with Metal Greymon.
And just when you think you can't get any more awesome, Mr. Kouji Wada goes and gives us "X4B The Guardian" for ShoutmonX4B's appearance. Xros Wars seems to be giving its main Digimon their own themes.
Not just the good guys, but the evil Digimon get their own themes too! Dark Knightmon has Dark Knight ~Immortal Champion. With lyrics like "KILL YOU" in it, you just know it belongs to a magnificently evil bastard of a villain.
The pattern continues with "Dancing Hero of the Skies! X5!", which sounds like something straight out of a Super Robot anime! (Complete with lyrics describing the transformation and abilities of Shoutmons new form!)
Now that evolution has been introduced, even more awesome songs are sure to follow, the first of which is Taiki's evolution theme, Evolution and DigiXros Ver. Taiki, perhaps the epitome of Hot Blood condensed into a single song, this brings Kouji Wada's songs for Xros Wars to four, which is his highest yet for a Digimon series, equal with Frontier. And he didn't even sing the Opening theme!
Xros Wars changed OPs for its second arc, so behold New World, the first Digimon Opening sung by a female singer. Its chorus leaps straight into ear worm territory.
And if you thought they couldn't top what they already had, they give us We Are Xros Heart - ver. X7 , sung by a seemingly impossible trio of Koji Wada, Takayoshi Tanimoto, and a returning Ayumi Miyazaki! Not to mention with this, Kouji Wada has sung a total of five (six if you count his small part in Kiriha's evolution theme) songs in Xros Wars, making it the most Kouji Wada songs in a single Digimon show! Miyazaki Ayumi wrote the evolution songs "Brave Heart", "Break Up!", "Beat Hit", and "The Last Element". Takayoshi Tanimoto wrote the themes for DarkKnightmon and Kiriha and his original entry into the song base was the much-beloved One Vision. There. Now you may return to bask in the awesome.