This is a high quality 27-track YM2612 soundtrack DLC (made by Hal "HeavyViper" Binderman) which you will find in Steam Music (Library>Music) or inside Zenodyne R's game folder under Zenodyne R OST. Comes with a free wallpaper.

Track List:

1. Envious Eyes (Title)
2. All Systems Green (Hangar)
3. A Single Spark (Stage 1)
4. Twilight Tactics (Stage 2)
5. An Ominous Aura (Boss 1)
6. One Light Among Many (Stage Clear)
7. Vicious Velocity (Stage 3)
8. Dawn of Determination (Stage 4.1)
9. DAI*GYAKU*SATSU TOREEN / 大虐殺トレーン (Stage 4.2)
10. Gaze Skyward and Scream (Stage 5)
11. It Froze my Blood White (Boss 2)
12. Never Let Me Go (Stage 6.1)
13. Lose The Fear (Stage 6.2)
14. The White of their Eyes (Stage 6.3)
15. Ancient Anger (Stage 6 Boss 1)
16. Gravitas (Stage 6 Boss 2)
17. SAI*KOU*SAIREN / 最高◊サイレン (Stage 6 Boss 3)
18. Supreme Tactical Ambush Buster-Armor 山◊並◊柾◊古◊SCHMIDT-XIII (Mecha)
19. See You In Hell!! (True Last Boss)
20. Space Cowboy (All Clear)
21. Hollow ~ Envious Eyes (Ending)
22. The Dying of the Light (Game Over)
23. Biorhythm (Continue)
24. Omake 3 MD Arrange (Omake 1)
25. A Corpse Can't Laugh (Omake 2)
26. NG1 - C'mon C'mon (Unused)
27. NG2 - Funky (Unused)