Consider:
A copy of the Hunter Tame/Stable system, where either within the Dreadscar Rift (Class Order Hall, would breathe life into past content) and/or next to the Warlock Trainer in every major city, there would be a “ Grimoire ” that functions like the Warlock stables.
Enslave Demon becomes like Tame Beast. Enslave Demon simply is never used. Literally never used. Only time it has been used in recent memory was as a gimmick within the Class Order Hall (where we didn’t actually enslave the mob, we just cast the ability and was auto-controlled into releasing us) and the Warlock Green Fire Questline (the Pitlord, which nowadays is irrelevant given gear level and the “of the Black Harvest” title no longer exists) and one of the adds in the Arcway dungeon during Legion. One of the times it was useful was to banish one of the mini-bosses in Hellfire Citadel, but then that was nerfed.
Each current demon becomes a “slot”:
- the Ranged DPS with Self-Dispell slot (Imp)
- Tank and AOE slot (Voidwalker)
- Melee DPS with CC slot (Succubus)
- Melee DPS with Interrupt and Dispell (Felhunter)
- Demonology Melee Cleave DPS with Tank and CC functions (Felguard)
Every time you enslave a demon it gets assigned a name you cannot change without dismissing that demon or enslaving the same mob again, following the same way all our default demons have assigned named and we have to pay to replace them. The only demons we could not “release” would be our default demons, maybe, I don’t know.
This would follow the logic that all demons are actually pre-existing beings. Our Wrathguard is an Eredar; he lived on Argus and had a family. They each have a “True Name”.
And canonically, knowing a demon’s true name gives you power over that demon:
Within the game there are already “families” of demons, and given the Voidwalker is a Void being ie aberrations families too. In fact, in the new Leveling Experience, we gain the ability to summon a Voidwalker by “completing” a ritual via a grimoire to summon a Voidwalker from the Void while a Void portal hurts us.
Wowhead
Investigate first expedition warlock’s corpse. A level 1 Exile’s Reach Quest. Rewards Learn Summon Voidwalker and Old Grimoire. Added in World of Warcraft: Shadowlands.
A Warlock’s Bargain Quest WoW
Infact, within the lore and earlier versions of WoW, grimoires were within the Warlock fantasy, whether was quest items where we enslave demons to learn them, or to empower some talents/spells:
Within the narrative, the only thing that prevents a warlock from enslaving a demon is our power. In Legion, we enslaved the Eredar Twins via a Bloodstone (which canonically is a fragment of Old God power), in the Legacy of the Masters questline (Green Fire quest), we enslave a Pit Lord when fighting Kanrethad at the end scenario, and to begin with as it stands we already enslaved an imp, a succubus, a mo’arg (Felguard), eredar (Prince Malchezaar, Demonic Tyrant, Wrathguard), a darkglare, an observer, a shivarra, a fel imp, a voidwalker, a voidlord (separate from the Void Lords that in canon cannot manifest in reality), a felhunter, an infernal, and an abyssal, and a variety of other demons through the Demonology Talent Demonic Portal (including Ur’zuls, and Felbats, and more)
Furthermore we are now the Netherlord of Dreadscar Rift, First of the Black Harvest, with a small demonic army at our disposal.
In the case of Demonology, the way the spec could be “unique” with regards to this hypothetical system is while Affliction and Destruction can enslave Common demons and aberrations, Demonology as a spec can enslave Elite/Named Elite demons and aberrations. Perhaps with a singular Destruction exception of their being able to Enslave/Tame Elite Demons for the Infernal CD, and Affliction being able to Enslave/Tame Elite Demons (or Aberrations?) for their Darkglare CD. But Demonology could enslave Elites for whatever demon slot