Hi!
Edit 4/22/23: one of these has been fixed on live, and another on the 10.1 PTR. I moved those to the bottom of the list and marked both as fixed/incoming fixed, as well as added the issue causing shadowfiend glyphs to not be removable with vanishing powder/reset to the glyphed appearance again on logout, if a workaround is used to unglyph them.
In order of impact / importance to be fixed:
1. Revel in Purity does not spread purge the wicked properly in about 40-50% of cases.
Since Revel in Purity’s entire purpose is to spread purge the wicked to a second enemy, it is frankly incredibly frustrating that this remains an issue that has seen zero acknowledgement/attempted fixes since DF prepatch. The talent never worked properly in beta and still does not work on live today. The issue with the talent is that, even when multiple targets eligible for purge the wicked spread are present, both instances of purge the wicked that are produced by casting penance will spread to the SAME target instead of two different targets.
The following seem to lead to a higher (but not guaranteed) chance of both new dots being spread on the same target instead of two different targets:
- The targets that ptw could spread to are not hit by the priest yet. Until a target is attacked by another spell, even if we are in combat with them already, revel in purity will not properly spread purge the wicked and will instead spread twice to one target, producing one singular 24s (max pandemic duration) ptw.
- If all targets but 1 have purge the wicked on them already, purge the wicked will spread twice to the ptw-less target guaranteed.
- If all targets have purge the wicked on them already, both new dots created by casting penance with revel in purity talented will spread to the same target. I don’t know if it’s still coded to work this way, but in legion blizzard stated that purge the wicked prioritizes spreading to the target with lowest duration remaining if all targets have ptw on them already. My guess is that this behavior still exists, and forces the two instances of ptw spreading to both go to the same target: the one with lowest duration remaining.
- This last one is the one I understand the least. It happens probably 25% of the time. For some reason, position relative to the target ptw is being spread from will mess up revel in purity and cause 2 dots to spread to the same target instead of 2 separate. This is most easily reproduced in valdrakken, as it happens easily with certain dummies within the 5-pack of them. It is not a dummy exclusive issue though, it happens in dungeons, in raid on broodkeeper occasionally, etc. I simply do not understand the criteria for this to happen, but it happens enough to be a pain point.
All of these factors combine to make a talent with extremely shaky functionality that simply is not excusable to still be live and without any fix in sight. Purge the wicked spreading is core to discipline’s ability to do damage / healing in aoe scenarios, ESPECIALLY now that we lost mind sear. The buff to rhapsody announced today does nothing to lessen the importance of fixing this. It affects our mana longevity (via Throes of Pain), it affects our damage, it affects our healing, it affects the ease of use of expiation, it affects basically every facet of the spec. Purge the wicked is often our highest damage source in any aoe situation, and I cannot stress enough how badly this talent needs to be fixed.
2. If Shadow Covenant is cast immediately after halo (or any time before it first does damage), it will not produce any atonement healing when it does damage.
To be clear, this is different than the issue that 10.0.7 fixed, which was halo doing the same healing whether in or out of shadow covenant.
3. If Halo is cast at the end of Shadow Covenant, and Shadow Covenant falls off just before the cast completes, the cast is completely canceled.
It goes without saying that this one is aggressively frustrating and needs to be fixed so that either we just get the shadow halo cast off, the same way penance works right now under the same condition (dark reprimand continues to cast even after scov falls off), or halo simply checks on cast completion for shadow covenant and fires off the correct version of the spell. I understand that since the spells are different spellIDs, its not as simple as having the cast be converted back to regular, holy Halo if shadow covenant falls off during the cast.
Added 4/22/23: Players who had their Shadowfiend glyphed before the change that allowed those glyphs to work with mindbender cannot remove the glyphs.
Until today I had forgot to mention the fact that, for players who had shadowfiend glyphed to Sha Beast/Lightspawn/etc before the change that made those glyphs compatible with mindbender, it is literally impossible for us to unglyph our pets.
The only way to TEMPORARILY remove glyph of the sha (for example) is to apply a different appearance glyph to Shadowfiend, THEN use vanishing powder. Vanishing powder cannot be used until a different glyph has been applied, as the game seems to not fully recognize the spell as a glyphed spell. Doing this unglyphs the spell until logout, which for some reason then resets the spell to the Sha Beast appearance. There is currently no way for affected players to permanently unglyph their pets. 
and this breaks weakauras made for shadowfiend/mindbender.
FIXED ON 10.1 PTR!!! 
: 5. Expiation is not affected by any of our damage modifiers.
This should have been fixed when expiation double-dipping with external damage modifiers was fixed, and frankly I was extremely disappointed that this wasn’t the case. In a random hotfix late on friday, expiation was:
- Nerfed by 30%ish (bugfix, and this is fine)
- Affected by damage reductions appropriately (bugfix, totally fine)
- ALSO lost its ability to crit, despite the fact that the dot damage it is condensing CAN crit. Not only can it not crit, it received no alternative crit scaling (like spirit shell had, where crit was just normalized into a % amp over the entire absorb produced) in place. Crit is our second best stat, and the talent is by no means overpowered in a non-bugged state. It is now lackluster and only used due to NO viable alternatives existing in our tree, now that Divine Aegis was over-nerfed due to being bugged on Raszageth stormsurges + us having Voidmender’s Shadowgem this season in raid.
- Was left STILL unaffected by both shadow covenant and schism.
To get my point across, let’s take 6 seconds of purge the wicked damage on my priest. purge the wicked ticks for 1800 base. This is increased to 2065 during schism, or 2374 if the ptw was buffed by twilight equilibrium. It ticks every 1.4 seconds, and has 25% crit chance. 6 seconds of this dot is 12700 damage on average. Expiation reduces purge the wicked’s duration by 6 seconds, and does…8582 damage. This is 67% of the expected amount.
In other words, expiation now reduces purge the wicked by 6 seconds to do only 4 seconds worth of damage
The easiest fix to this would be to restore crit scaling to expiation, and to ensure that it is affected by schism. It is shadow damage and should be affected by shadow covenant as well imo, but since it is affected in the event shadow word: pain is used (literally never) due to using the dot’s damage to calculate expiation’s damage, I can respect blizzard not allowing shadow covenant to amp expiation’s damage, due to its potential to double-dip if shadow word: pain is used (again, literally never).
FIXED: * 6. The renew buff that was supposed to take effect when 10.0.5 released did not not actually buff renew’s healing over time.*
This one is the only one I cannot personally check or substantiate but I am reporting it here since the disc theorycrafters have said this is the case and they generally are reputable sources.
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I and many other disc mains are going to be hoping blizzard sees these issues and addresses/resolves them before this season is over. People come into the disc channel of the priest discord frequently asking about revel in purity being bugged or even not realizing what it is supposed to do, fairly frequently. Can’t stress enough how far fixing that bug would go with smoothening our gameplay in multi target situations.
Please fix these. I understand we are one of the least played specs but there are still thousands of us. If even just one of these was fixed (hopefully Revel in Purity), it would go a long way toward making the spec feel more user-friendly.
Thanks for your time.
-Psy
UPDATED 4/22/23
Thank you blizzard for fixing two of these so far - I now actually have some hope that revel in purity will be fixed…hopefully soon.
…God I hope it’s soon.
