After the quest, new replacement NPCs appear since Lucien killed most of the team of RS gold warriors organised to stop him in the Wilderness, although there is no replacement for Hazelmere or Cyrisus.

Turael -> Spria
Duradel -> Lapalok
Ghommal -> Laidee Gnonock
Sloane -> Yadech Strongarm
Lucien -> Local Thug and Local Mage
Mazchna -> Achtryn - only during the quest

Music unlocked

Audio options icon
Temple Desecrated
Music unlocked during While Guthix Sleeps.

Dangerous Logic (after entering table trapdoor)
Black of Knight (in the Black Knights' Fortress dungeon)
The Evil Within (in the cutscene where Lucien slays the heroes)
The Sound of cheap OSRS gold Guthix (in the Ancient Guthix temple)
Temple Desecrated (at the battle with the Balance Elemental near the Stone of Jas)