This guide will look at some of the frequent errors that the raiding Holy Priest encounters and how to correct them. This guide will continue to receive updates for more specific raid encounters in Uldir.
Holy Raiding: Fundamental Importance
Holy Priest's most frequent issue when analyzing logs is often their fundamentals. These, captured below thanks to the WoWAnalyzer site,show the total uses of each ability, their time on coooldown and the maximum potential casts that the Priest could have had. These three abilities make up a substantial portion of Holy's healing and are often some of the most efficient tools that are available to the specialization. As such, it is imperative to identify when you are holding onto your abilities too long and working to use them more often. With your Holy Words it is important to note that you should also not be overhealing with them just to reduce the cooldown of Holy Word: Sanctify. Frequently you will see Holy Word casts look similar to the image below where almost all of the casts are utilized on cooldown, but damage patterns and downtime can prevent 100% efficiency.
Prayer of Mending on the other hand, is an incredibly important ability to maintain on cooldown whenever possible and has no real restrictions on when to cast it. In an ideal world your Prayer of Mending casts should look very similar to the image below when you utilize the Cast tab on the far right in WarcraftLogs. The height of these bars does not matter, but the spaces in between each bar does. In it you will see the gaps in between each cast where perfect usage will have gaps of about the same length in between them. The blue bar in the background at the start and halfway through the encounter is the Bloodlust buff which grants the Haste that reduces the cooldown of those Prayer of Mending allowing more casts in that period. After Lust, the spaces maintain a fairly consistent distance between each other for the rest of the encounter.
Holy Word Accuracy
While it is key to be casting Holy Word: Serenity and Holy Word: Sanctify on cooldown as often as damage allows, it is also key to look at the accuracy and effectiveness of both abilities. In WacraftLogs or any damage meters addon like Details or Skada you can check the overhealing and the accuracy of both Holy Words. Accuracy for Holy Word: Serenity is almost entirely based on its overhealing which should be kept to a minimum whenever possible, while Holy Word: Sanctify must look at the overhealing and the number of targets hit per cast.
Holy Word: Sanctify hits a maximum of 6 targets per cast, so like in the image below you can see the first number circled on the Left as the number of casts (15) and the number on the right as the quantity of allies hit by Holy Word: Sanctify (86). With some quick math you're able to see that 86/15 = 5.73 players hit per cast, so almost perfect usage of Holy Word: Sanctify with very limited instances of a 6th player being missed by the ability. This may not be an issue at all if you are on a stacked encounter or have a great deal of melee, but this can be important to quickly check to ensure you are being as efficient as possible.
While this is a common factor for all healers, Holy Priest, in particular, have such a broad toolkit that it can be easy for an inexperienced player to quickly burn through mana in an inefficient manner in order to get their Holy Word: Serenity, Holy Word: Sanctify or even Salvation off cooldown in a faster manner. An excellent rule of thumb that is well highlighted again by WoWAnalzyer is the chart below which compares the health of the boss to the player's mana over the course of the fight. An ideal log will have those two tracks trend fairly close together. From this log, we can see that the mana remained close together overall but key moments the player's mana dropped faster than the boss' health in order to deal with spike damage.
In order to maintain a fairly consistent trend though, the Holy Priest paced themselves in downtime with very consistent Prayer of Mending casts and Heal as filler to allow mana to regen while still reducing the cooldown of Holy Words in the most mana efficient way possible. So even with significant gaps at 1:30 and 4:30, the player still succeeded in their end goal of using all of their resources by the end of the fight without going oom (out of mana) before then.