Here's some of my personal faves.

Rise of the Triad, Composed mostly by Lee Jackson of Duke Nukem 3D fame, with some songs by Bobby Prince of Doom and Commander Keen fame. This soundtrack is one of the most well crafted MIDI Game Soundtracks of all time, even better than some Doom tracks (Though not nearly as iconic). The Soundtrack has an orchestral feel to it, despite being made with MIDI sound libraries. There's a grandiose, yet playful feel to most tracks, which I love. Tracks are generally short, but loop very well and it's difficult to get sick of them. If you watch Retro FPS Reviewer Civvie 11, some of these tracks might sound familiar, as he uses the soundtrack extensively in his videos, including his old Intro, as well as his current Outro.

Goin' Down the Fast Way, used in the First level of the Shareware Exclusive chapter, The Hunt Begins, this is the most iconic ROTT track to some. It is very high tempo, getting you in the mood to shoot some totally-not-nazis with various explosive weapons. It is a complex composition with a lot of layers, and sounds amazing even now.

Oww!!! is, for lack of a better word, an absolute banger, with a very groovy guitar mixed with lovely synths.

There's a great deal of Classical Rearrangements in the soundtrack, including Funeral for Queen Mary, God Rest ye, Merry Gentlemen (Though this one is more of a reimagining, and it remains on top of my list of Christmas Ass-Kicking Bangers), as well as my personal favourite, Adagio for Strings, which is also a reimagining, pairing a gorgeous drumbeat and synths alongside a classical masterpiece. Immaculate.

Also check out Andrew Hulshult's Remix of the Soundtrack for the painfully mediocre 2013 remake of Rise of the Triad, which is saved by Andrew's Soundtrack, that leans more into Metal than Orchestral, though there are still some orchestral leaning songs!

Another one of my favourite Soundtracks is also a retro FPS series, Unreal 1998, as well as the first in its lineage of the more successful spinoff, Unreal Tournament. The soundtrack is composed by Alexander "Siren" Brandon, who worked on Epic's earlier games, such as Jazz Jackrabbit, as well as Tyrian, and later working on Ion Storm's Deus Ex, along with the other major composer of the first 2 Unreal games, Michiel "M.C.A" van den Bos. Unreal Tournament also features some guest composers such as Andrew "Necros" Sega, Peter "Skaven" Hajba, and Dan "Basehead" Gardopée. The first two Unreal games utilised Tracker music, and all the composers were very experienced in this format. There's a good variety of genres in here, and each track feels wholly unique.

Ending, composed by Brandon, was initially designed to play in the main menu, before being replaced with the Castle flyover animation, which had its own music composed for it. This track is grandiose, utilising many gorgeous sounding samples, and is befitting as both the start of an epic journey, as well as the end. It is otherworldly, and beautiful.

Shared Dig is a bopping tune with a sturdy beat to it, befitting a mineshaft where plenty work was done. One interesting fact of note is that Unreal has a Dynamic soundtrack, with certain sequences in a tracker file set to play during certain places. the part at 2:34 plays during a tense encounter with a new enemy, a Skaarj warrior, which flips the track on its head during a tense, cramped fight for survival. I adore dynamic soundtracks. It always hits for me.

Nightvision is an utter banger composed by Brandon, which was retooled to use in the game. It's intense, high tempo track which gets you raring to go, and just sounds so fucking good. I really wanna hear this played in a nightclub. It goes so hard.

Over in Unreal Tournament, Foregone Destruction is definitely one of the series' most famous tracks, Composed by van den Bos and played on the famous Capture the Flag map, CTF_Face, also known as Facing Worlds. It is the face of Chill DnB, a serene synthbeat with a bangin' amen break. Gorgeous, and iconic.

Mechanism 8 is one of my personal favourites in the series. I'm not as well versed on music terminology as i should be but the siren-y sound played throughout the whole track makes the track feel like part of a gigantic machine, mixed with a bangin drumbeat, and beautiful samples. It's difficult to put into words all the parts that make this song such a memorable one for me, but it stands that this track is beautiful and I fuckin' love it.

Save Me is in my opinion a testament to how strong a short loop can be. It is one minute and thirty seconds long with a ten second intro, but it's utterly mesmerizing, no matter how many times it loops. The distorted guitar gives this track such a unique, feel, an intense explosion of energy that never fails to give me goosebumps. Check out this looped version!

There's so many tracks in these two games that I love and I'm running out of words to describe how much I love them, so i'll just throw a bunch more in your face. Interlude II - Unreal, Return to Na Pali, Surfacing - Unreal, Three Wheels Turning - Unreal Tournament, Razorback - Unreal Tournament, Seeker - Unreal Tournament, All Hallows Sunset - Unreal.

There's other soundtracks I wanna talk about but this post is already long enough so I'll leave it at these 2.