decrease the mana cost (Either though proc based cost reductions or straight percent cost reductions) will be your priority. Other talents should only be picked as fillers to get to the next tier.
Shaman – Two spells will be your main healing spells – Healing Wave and Chain Heal. Any talents that improve these two spells will be priority. Mana efficiency will be your next priority. Filler talents are, again, used only to get to the next tier.
Druid – Heal over Time spells (HoTs) are your main focus with Druids. Rejuvenation and Regrowth will be the two spells you will use until later levels. Nourish, Wild Growth, and Life Bloom will be added as additional tools later on. Talents that improve these spells will help you out the most. Make sure to get Tree Form as soon as you can. Lastly, do not get talents to improve Healing Touch. This should only be used in emergency situations and almost always in conjunction with Nature’s Swiftness.
Priest – Priests are the only class with two talent trees dedicated to healing – Holy and Discipline. Holy is considered better at multi-target healing while Discipline is better at single target healing. Holy uses Heal and Greater Heal as its main heals with a Holy Nova or Circle of Healing thrown in for when it is needed. Talents that improve these spells will be your main priority. Discipline uses Power Word: Shield and Renew as its main heals. Talents that improve these spells will be your main priority.
There you have it. Leveling through Random Dungeon Finder as a healer can be a very fun experience. Druid is my favorite class to level in this way. Yours may be different. Always remember, pick the class that best fits your play style and you will have the most fun.
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