Orb is the song composed by Kevin Schilder for Hexen: Beyond Heretic.
Hexen: Beyond Heretic (DOS)
Orb plays at the startup when the game loads its resources before entering the main menu. If the game is done loading (which is usually a fast enough process on a fast machine) Orb stops playing, so many players do not manage to listen it to its end except for listening the MIDI (or CD) version or on VGMPF.
When the game finds the CD inside the CD-ROM, it plays the track number five which is Orb itself. Also, the CD version is played when showing the victory scenes at the end of the game.
Hexen: Deathkings of the Dark Citadel (DOS)
In the expansion pack of the Hexen, Orb is also played at the startup screen and in the other same points of the game without differences.