Priests are often frustrated that other classes do not appreciate how to work with them, and its very much in your interest to know how to work well with your priest so that your groups are more successful, wipe less often and you finish more quests and level faster. You may be reading this as a non-priest because someone you have grouped with suggested you do so, please take this stuff on board and you will enjoy the game more when grouping with a priest.
I have put together my thoughts on the things you need to bear in mind when grouping with a priest.
In Wow each mob you are fighting will attack whichever character with which it has the most hate or aggro. Different members of the group build hate through three main methods.
Now this is important if you have a priest in your group. Say your group pulls 3 mobs, those 3 will attack who ever they have the most aggro with. So lets say these 3 mobs come running over, mob1, mob2 and mob3. If your party attacks only mob1 the priest is put in a difficult position, and they can do one of two things. Because they only wear cloth armor they can not afford to be attacked by drawing aggro, so if your group is attacking only one of three here are their two options.
The conclusions is that in wow you should insure that you build up sufficient hate with all mobs if you want to be healed, if you see your priest being attack immediately turn and attack the mob which is hitting on the priest so that it turns to fight you again. Always keep one eye on your priest and never say all on one mob.
A good mage will keep a mob sheeped, this is sort of an exception to the above rule, however many mages fail to realize just how powerful this spell is, so mages, check it out.
Your priest can heal you but only if he can see you. If you have taken damage a decent priest will always know and do everything they can to heal you, however if you run wildly around from room to room then the priests healing spells will continually fail because you keep running out of his line of sight. If you want to be healed stay still in front of the priest.
A priest can only heal if he has enough mana to do so, so keep an eye on their mana bar and listen for OOM (out of mana) shouts. If your priest shouts OOM during a fight if you immediately go and enter another fight straight after you can expect little or no healing.
Many priests have an ability called Spirit tap. If your priest asks always when possible allow them to kill a mob on very low health, not always possible I know, but if a mob is running away with just a sliver of health left toward the back of your group where the priest is anyway let the priest kill it. The spirit tap ability allows the priest to almost double their mana regeneration for 15 seconds. This means that the priest will have more mana to heal with sooner.
Priest can deal damage and they can also heal, however they can't do both at the same time, I doubt your priest is standing at the back of your group is doing nothing, more likely he is renewing you and therefore is not in a position to be wanding the mob as well.
For this priest and many others our favorite healing spell is called renew, this spell does not just replace a huge chuck of health at once, but instead it repairs damage to you over time. So every 3 seconds you will get x hp repaired. The reason we like this so much is because it's a) mana efficient when we spend talent points on it and b) it does cause aggro like a regular healing spell except the aggro it causes is spread over the duration. As such this allows the tanks to gain their own aggro up with the mobs and avoids the priest getting hit on.
Sometimes however, the opposite will happen, and you be fighting while your health gets lower and lower and the priest is still wanding away. For a priest how to heal is very much taste and philosophy. Some take the little and often approach but others prefer to use a big heal like greater heal when your health is low. So don't start calling for help when your health goes below 50%, the priest may be waiting for the right time to cast a big heal on you. However if your playing with this sort of priest make sure you manage that aggro. A big heal may take 4 seconds to cast but every time a caster gets hit it partly resets their cast time. If they get hit often enough they may never actually finish their cast time. If you can't manage aggro, they can't heal you.
A lot of tanks hate getting shielded as they believe it stops them gaining rage, however this is not true, testing posted on the US forums has shown that shields do not have a significant if any effect on rage generation.
Also and more legitimately a warrior dislikes shields as they believe it draws a lot of aggro to the priest for them to get off. Partially true, a shield generates only half the amount of aggro that a heal does for the same HP's, a shield is very useful when used right. If the priest cast shield before a fight has begun it draws no aggro, and reduces damage taken by at tank at first, usually by the time a priest is called on to start dishing out heals he has regenerated that mana spent.
Furthermore it's instant cast, if a tanks health is really low an instant shield, an instant renew then a few seconds to brew up a nice big heal can be mana costly and gain hate, but it could also save the tank when in a tight spot.
A priest is watching your health at least as closely as you are, constantly asking for heals when going under 30-40% health is like saying your priest is incompetent and an insult to us.
I appreciate that this is an automatic function on some add-ons, but please turn it off, otherwise every time you get into a fight your priest will start spamming "Fight" and "Hit the mob" over and over again.
A common misconception, priests don't forget to heal you, they let you die. Sometimes they simply can not heal enough of the party if a pull goes bad. In this case a priest first concern is to prevent a wipe of the group, and this largely means healing the main tank, other party members may have to be sacrificed and rezzed later.
As I mentioned above the priest first concern is to prevent a wipe of the group. Sometimes its obvious that you simply are not going to win whatever nightmare fight you have got yourself into. At which point a priest may very legitimately run and hide until the mobs leave and return and rez the group. However, in some cases, the priest has already attracted aggro and knows he will never get away. At which point he may see another class which can rez running away, so a clever priest will do everything he can to insure they get away. My brother plays a druid, so I know if it all goes down and he gets away he can return and rez me then I can rez everyone else, strangely priests do have some spells that draw massive aggro so in that case I will use them and heal my brother so that he can escape and shadow meld until the danger has gone.
Everyone is entitled to take what they will use. However what you WILL actually use yourself is not the same as what you CAN use. If you really intend to wear something do say, but if you're just going to vendor an item then the priest is just as entitled to roll on it as you are. A priest can only wear cloth so most items dropped he cannot use, however he still has to buy spells to heal you with and these cost money.
A priest needs buffs just as much as you do, when grouping I always ask party members not to worry about giving me attack buffs but armor buffs and mental buffs like Arcane Intellect are sorely needed. Mages this also applies to your water.
If you can, heal. Say you're a pally or druid remember that when the @#!t really hits the fan the priest is going to be intent on keeping the main tank alive, sometimes he can be chain casting to do just that. He may not have time to do anything else. So, if you can, heal yourself in a tight spot.
Make sure you put that soulstone on your priest rather then yourself, because your priest can then rez everyone else.
Remember that we can not see your pets health like we can see the groups health bars, we have to manually target your pet to see its health, and guys remember when the fight gets hairy we have a lot on our plate, however there's no harm in asking "can you heal my pet" every now and again, because we may just have not had time to check it.
There is nothing worse then getting through an instant getting most of the way there then dying, only to discover that the two pallys you have with you haven't bothered to do the quest to get resurrection. Do the quest, pretty please.
Read the forums, ask for and listen to advice from other priest and definitely check out this post from the US every good priest should know Remedy's work backwards.
You may believe that none of this matters. However, bear in mind that while you can get away with it now at higher levels, having a priest in your group can really make a difference, even at lower levels if you offend a priest enough he or she will never group with you again. I'm lvl 26 right now, and usually with 2 minutes of logging on I will receive 2 or 3 tells from players asking me to join their groups because I have healed well for them before, those players who have looked after me I will do my up most for, however those that I have grouped with and completely break every above rule I will remember. Please guys, we are a supporting class and we choose this role because we enjoy helping, so help us help you.
Elunia, Night Elf Priest of Stormrage Realm
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