Just like your title mentions, this is a battle theme, meaning that as long as you are using Vergil as a character (or have selected his theme in the Jukebox), then in almost every normal enemy encounter this song will be playing in the background. The battle music in the game is dynamic, meaning that depending on your current style rankings, different parts of the songs play. For example, from D to B rank, the verses play (Immortal temptation../Inherit the nightmare..), then on A rank you get a drum and synth build-up and as soon as you hit S or anything above it, the chorus starts playing (I am the storm that is approaching.../Forsakened, I am awakened...). Needless to say, it's an amazing feeling to hit an S rank and have the chorus drop for all battle themes.

Fun fact: The last 3 minutes of this song were born out of pure love for the series. Casey Edwards himself said that Vergil is a very important character to him and that he didn't know if he'd get the chance to compose for DMC again. The first 6 minutes were all that was needed, the song was complete. He could have sent it off to Capcom and they'd be satisfied. But he wanted to give a final statement to Vergil and a goodbye to the series. So if you've ever wondered why that part feels so fucking raw, it's because it is. The emotions there are 100% sincere.

bro turned into a tomato when the beat dropped

For this song, Casey Edwards was giving a restriction by Capcom that, with the exception of the Chorus and the outro, he was not allowed to use Distorted Guitar. His reaction? "Okay, then I'm just going to use the filthiest Bass tone I can create, throughout the entire thing."
He created an incredible track, with Victor Borba leading the vocals (who started out as a YouTube cover artist, btw), and it just captures every high and low of Devil May Cry and the character Vergil. Such an amazing song, and I've basically been listening to it on repeat since release. Casey can do no wrong!

This song is just 2 words. Pure MOTIVATION

Something that not many people notice: the final lines of the song starting at "Bury the light deep within" line up to the melody of Devil Trigger's chorus, easiest to hear being at the lyrics "Embrace the darkness that's within me." If you line up the syllables and the way they are sung, you can sing "within" at the same time in both songs. And the rest follows the same way.

Bro the last battle against his twin brother (Dante) is EPIC, I still play this game and the epic battle with this music <3

The vibe in game is FANTASTIC. As the title of the video suggests it's a battle soundtrack, so when you use Vergil you're gonna hear it always during a fight

Fun fact:
SIGNIFICANT MOTIVATION

It's such a well balanced song.  I'd say it's as close to perfection as you could get in terms of production.  Such a massive song.

This Song is Just incredible

Some previous commenters mentioned that this song was made specifically for Vergil but haven't been able to talk about all the layers behind how true that is. Everything from the dark oppressive tone showcasing his brutality to the violins that symbolize an almost obsessive precision is Vergil. And then we get to the last part of the song with the "lurking in the shadows under veil of night" - this part was a reference to the song in DMC 3 "Devil's Never Cry" which was our first real introduction to the character. Finally we have the last lines of the song "Bury the light deep within" - this part is, note for note, the same as the chorus in Nero's theme in DMC 5 "Devil Trigger" which is so cool considering the character connection there which I will not spoil.

this goes to show how game music is evolving beyond people's expectation, This piece of music is a masterpiece and it fits perfectly with the Best action game that I ever played which is DMC5, especially when you're just Cutting and Styling on demons left and right with Vergil as this plays in the background. Great game, would totally recommend

Playing as Virgil is probably the most awesome feeling ever

I love watching people react to this since i literally had the same reaction lmao.

great feels and a gut-drenching song takes a lot of hard work to accomplish masterpiece like this ......great reaction bro

this song is fantastic, it make you want to fight against the god and very motivate. Btw nice reaction man!

I don’t think I’ve ever seen a reaction to this song that hasn’t been like “this is the greatest song I’ve ever heard” or close to

The music is Vergil's personality itself

now i'm a little motivated