The tracks that comprise the first volume of '''''[[Ghosts I-IV]]'''''.
===10 Ghosts II through 18 Ghosts II===
The tracks that comprise the second volume of '''''[[Ghosts I-IV]]'''''.
===19 Ghosts III through 27 Ghosts III===
The tracks that comprise the third volume of '''''[[Ghosts I-IV]]'''''.
===28 Ghosts IV through 36 Ghosts IV===
The tracks that comprise the fourth volume of '''''[[Ghosts I-IV]]'''''.
===[[999,999]]===
The first track on '''''[[The Slip]]'''''. No other versions of this song appear on any halos.
===[[1,000,000]]===
The second track on '''''[[The Slip]]'''''. A version of this song appears on the bonus DVD of the physical edition of '''''[[The Slip]]'''''.
===[[10 Miles High]]===
A '''[[NIN]]''' song that initially appeared on the vinyl edition of '''''[[The Fragile (halo)|The Fragile]].''''' Versions of this track can be found in the UK version of '''''[[We're In This Together (halo)|We're In This Together]]''''' and '''''[[Things Falling Apart]].'''''
===[[105th Airborne Crusaders]]===
A military unit formed in the fictional world of '''''[[Year Zero]].''''' The unit seems to have formed after the bio-terrorism attack in Los Angeles that is described in the '''[[Hollywood in Memoriam]]''' website. Members of the unit seem to all share a deep belief in Christianity, and use their faith as motivation in the war.
===[[10 Miles High]]===
A '''[[NIN]]''' song that initially appeared on the vinyl edition of '''''[[The Fragile (halo)|The Fragile]].''''' Versions of this track can be found in the UK version of '''''[[We're In This Together (halo)|We're In This Together]]''''' and '''''[[Things Falling Apart]].'''''