A core choice at the start of your journey in the Shadowlands will have you decide where your allegiance lies; would you rather support the Kyrian of Bastion, the Necrolords of Maldraxxus, the Night Fae of Ardenweald, or the Venthyr of Revendreth?
Choosing a covenant is the most important decision your character will make in Shadowlands, as the covenant abilities and Soulbinds will significantly impact your spec's gameplay and performance. Through this choice, your rotation changes, certain bonuses appear in dungeons for your entire group, and you are able to follow the story in different paths.
So without any further ado let's get right into it;
Due to the Sanctum of Domination raid being heavily single target based, Venthyr will be the best option for the raid when it comes to single target especially when paired with the Frost Shard Set.
Necrolord is the second best choice for raiding and can even pull ahead on fights where there are adds/cleave.
AoE / Mythic +:
Assassination Rogue's go to spec for Mythic + is Necrolord it pulls ahead over Venthyr in multi-target scenario.
However again, Venthyr is not too bad, but if your main focus is on Mythic + or if you're progressing raid fights with cleave/adds we recommend going Necrolord.
When it comes to PvP, Necrolord is by far the best covenant choice for Assassination Rogue, the tankiness provided by the Soulbinds as well as the Fleshcraft shield, combined with the damage buffs from Kevin makes Necrolord the best covenant choice for PvP
To sum this up, due to the nature of the Sanctum of Domination raid being heavily on the single target side Venthyr will be your best choice for Single Target, as it is the current best single target option, but if your goal is to do more Mythic + or progress AoE based fights, we recommend going Necrolord.
Outlaw Rogue has a bit of a different viable options when it comes to raiding and single target and they all come in close to each other while Kyrian is pulling slightly ahead on single target.
AoE / Mythic +:
It seems like all Outlaw covenant can see some play in Mythic + scene with more people leaning towards Necrolord
Kyrian and Venthyr are also close by.
When it comes to PvP, Necrolord is by far the best covenant choice for Outlaw, the tankiness provided by the Soulbinds as well as the Fleshcraft shield, combined with the damage buffs from Kevin makes Necrolord the best covenant choice for PvP
As there are many different covenants you can play Outlaw with we recommend going Necrlord as its the best median covenant for all aspects of the game.
When it comes to single target, mythic + or pvp Necrlord is the easy choice
For single target or raid options you would want to opt into the Venthyr covenant as it has the best single target damage for raid encounters.
AoE / Mythic +:
And for Mythic + / AoE Venthyr is again your only really viable option. You can get away with playing Necrolord but we highly recommend Venthyr
For Subtlety Rogue for any aspect of the game everything is going to be Venthyr and PvP is no different, the amount of burst you can do with the covenant ability makes every rogue setup a scary one, being able to quickly withdraw with Door of Shadows also helps you recover
To quickly sum this up, for most aspect of the game for Subtlety Rogue you're going to want to play Venthyr as it has exactly what Subtlety Rogue needs.
Covenants have a major impact on the game, your playstyle, rotation and even character aesthetics. You should consider all your options before committing to one covenant.
But also remember you can switch between covenants so if you would like to change between them you can!
As of current there is a time gate on how you can switch covenants but with the release of patch 9.1.5 it will be much easier
Remember! You will lose access to all your previous Covenant’s abilities, transmogs, and soulbinds
It is a bit tricker to rejoin a covenant you have already left and it will require a bit more work. In this case, you will need to complete two consecutive weekly quests before you will be allowed to rejoin.
The leader will then give you a weekly quest to start the process of rejoining the Covenant by completing quests in the covenant zone or dungeons and you will see the progress bar fill up as you finish various tasks.
Once you finished the quest and the Weekly Reset has happened you will be given yet another quest, the objective of the quest is pretty much the same then you will be able to rejoin the covenant.
In total it takes about one weekly reset to rejoin a covenant you previously left, so make wise choices!