One of the longest-running game composers, Jesper Kyd has been producing bangers for over three decades, contributing to the Assassin’s Creed series, the Borderlands series, classic Genesis shooter Sub-Terrania, Gears of War, Splinter Cell: Chaos Theory, and many others.

Speaking to Polygon below as part of our weeklong look at the crossover of games and music, Polygon FM, Kyd described his memories of the early days of game music on Commodore 64, his influences and process working on Assassin’s Creed games, and the importance of atmosphere when working on game music.

Polygon: Was there a game soundtrack or song that inspired you to pursue creating game music? Can you set the scene of what that felt like for you, and why the music was so effective?

Jesper Kyd: I fell in love with game music on the Commodore 64 back in 1985. Video game music was revolutionized on the Commodore 64. The analog sound chip inside the C64 allowed composers to achieve atmosphere and emotion, and a new music style was born, which today is known as chiptune or chip music. Favorite game soundtracks from back then were The Last V8, Parallax, Wizball, Mutants, Light Force, Warhawk, and many more.

Parallax included a 12-minute main title masterpiece by Martin Galway. Hearing that for the first time is probably the moment I fell in love with game music. The amount of soul and creativity added to what could easily have been a one-minute loop was so spirit awakening to me. I thought, “Here is someone going for it with everything they’ve got, and putting a piece of their soul into this music.” That became my mantra, and I have worked with this philosophy on my own music ever since. To capture the core essence of the game, while adding a piece of your own soul, that’s what I try to do when inventing new music styles for games.

When starting a new project, I don’t know how my music will blend with other styles — such as the Italian Renaissance for Assassin’s Creed 2 — until I actually start working on the score and blending my music style with the new project. In many ways the music starts with a blank canvas and then I decide what elements to bring in and mix together with my writing style. So for me it’s also very exciting to hear what this new music style will end up sounding like. I am a big fan of this approach of starting with a clean slate (does it need dance music, or perhaps a symphonic score with live orchestra, or perhaps a folk music approach, etc.), so that adds so much excitement each time I start a new score, to see where the music will take me this time. I feel this raw emotion of excitement is one of those things that enables me to pull from a huge unlimited well of creativity, that I can feed from for each new score. But it does require having me always work on new projects for it to work best. I have followed this approach on Hitman, Assassin’s Creed, Borderlands, State of Decay, Darksiders 2, Warhammer: [End Times -] Vermintide, Dune: Spice Wars, Tumbbad, [Raid: Call of the Arbiter], Warhammer 40,000: Darktide, State of Decay 3, and many more.

Can you break down one of your own songs and its influences? Was it inspired by game soundtracks, other music, or something else?

[“Ezio’s Family” in Assassin’s Creed 2 was] inspired by the tragic death of Ezio’s father and two brothers, publicly hanged in the city square for his father’s association with the Assassin’s brotherhood. This moment defines Ezio’s life; it’s a core pillar of who he is becoming and we are there with him as it happens. I felt in this moment I needed to understand his mindset to best represent Ezio, and so “Ezio’s Family” was a composition that embodies the tragic events in this life and it became the centerpiece for the rest of the score. It enabled me to find a way in to his world and the rest of the score was built from there.

What are the main instruments used to record the soundtrack for the Assassin’s Creed series? How did you choose those instruments?

The main instruments [have changed] for each of the five Assassin’s Creed scores I have written. For AC1, the [cities] of Acre and Damascus each had their own instrument sets and Jerusalem was a melting pot of both. Acre consisted of live choir including religious chants, guitar, and violin-type string instruments as well as piano, harp, flutes, fiddle, and some orchestral instruments. Damascus dove deep into the ethnic instruments of the Middle East such as ney flute, buzuq, oud, duduk, and percussion like tabla, doumbek, frame drums, etc. This was also in relation to the three key words the team gave me: mysticism, war, and tragedy (of the Third Crusade). These elements were also carefully interweaved [sic] into the score. Furthermore, the Animus and its effect on the music also needed to be established, and I looked at it as a filter which all the music runs though, which filters and warps the instruments and soloist performances. Furthermore, the scenes of Altair being chased across rooftops with the screen tearing, that was when the Animus was being pushed to its limit and here the music style switched to sci-fi music which includes beats and synths with an orchestra mixed in.

For Assassin’s Creed 2, I worked with renaissance-inspired instruments; opera and vocal performers; as well as a live orchestra, choir, and synths. The focus was on a more youthful and playful sound following the prime of Ezio and his adventures.

AC Brotherhood was a more masculine and aggressive sound, and written around the concept of Ezio now being a master assassin, while style-wise following many of the same instrument inspirations as Assassin’s Creed 2. The game very much felt like a spiritual sequel to Assassin’s Creed 2. The Borgia family played a huge part in the story, and they were represented with an ultra bass choir recorded in a church. We also recorded a lot of percussion here, and one of my favorite recordings [was] the renaissance flags we swung in synchronization to create a cool, windy beat with a big church atmosphere. This music plays when climbing a giant castle and stealthily traversing inside as well. It turned out really cool.

For Assassin’s Creed Revelations, my music was deeply inspired by Greek music, which was the predominant music style in Constantinople at that moment in time. This sent me on a journey working with bouzouki; hammer instruments such as zithers, dulcimers, and the giant cimbalom; as well as Greek percussion, slide bass, GuitarViol, [and] ethereal and ancient-inspired vocal performances.

The first four Assassin’s Creed games used a similar recipe for the Animus and its influence on the music. Live performances are tweaked and altered, and the music in general includes light electronic instruments and elements to ‘sci-fi up’ the score.

For Assassin’s Creed Valhalla, I acquired a bunch of ancient instruments, some of them over 100 years old. Viking instruments such as the tagelharpa, tagelharpa cello, rebec, lyre, all types of horns and also some violin, cello, and clarinet played in unusual ways. And then male folk vocals and strong, powerful female vocals.

The idea this time was based around the concept of being outside in vast areas with mountains, hillsides, rivers, and so on. I decided to challenge the more city-based approach to my earlier Assassin’s Creed scores and created a music style that was inspired by the Nordic gods. Vikings were hugely inspired by their belief system, and I decided to make that the core of the score. So when you are exploring the world as a Viking, the score fills you with a sense of wonder and mystery. We also recorded a lot of instruments literally outside to get the added noise in the recordings. Furthermore, the Animus influence was reinvented, and I decided to perform the live instruments myself and base the entire score around these live performances. So no electronic elements or synths to symbolize the Animus. After the live performances were recorded, I had my foundation and then started heavily filtering and tweaking them. Then we would record with percussionists to get authentic drums and percussion. This modern approach became the Animus influence, and this approach of performing most of the instruments myself was a first for me.

Is there anything else we should know about your approach to composing video game music?

Emotion and atmosphere are the key ingredients I work with, as well as harmony and melody. For me, they are both equally important. For example, with the Imperium’s theme for Warhammer 40,000: Darktide, the glorious feeling of that theme is of course important to get right, but the underlying atmosphere of anarchy, pride, the hive city, the religious untouchable Imperium, getting all that in there does a lot to shift a classical-sounding choir performance into a gritty, far-future sci-fi world ruled by the Emperor of Mankind.

All the music choices throughout this track come from a far future place where war is eternal. You might not even notice these elements at first, but it’s all centered around creating a specific mood that the theme can live in. And it might take a few listens before realizing the reasons behind the instrument choices, etc. and that leads back to what I mentioned about creating music without dumbing it down and designing it for repeated listens.