Priest / Legion changes Holy . Given the innate purity of the spec , we want to ensure that holy priests continue to have a large repertoire of compelling healing spells . The Chakra system was cumbersome , requiring additional setup to optimally use most spells and restricting how much you could fluidly shift between healing methods . We have removed it in favor of a more dynamic play style focused around Holy Words . New Holy Word spells are designed to feel absolutely miraculous , having huge effects balanced with long base cooldowns . The new passive effect of Serendipity allows those long base cooldowns to be reduced , letting you use them more frequently . Finally , in keeping with the resolute beliefs of the holy priest , they can make no use of Shadow spells . Smite , Holy Fire , and are the instruments used by Holy Priests to inflict damage upon their enemies . Here ’ s a basic look at the core combat healing abilities for Holy Priests : Additionally , to give you an idea of how some talents may build upon this , here ’ s an example of one of their Holy - specific talents : Shadow . We ’ ve long alluded to the Old God influences of shadow priests in their spells and abilities , and we ’ re making that more distinct in Legion . A new resource , Insanity , provides a better fit for shadow , having more granularity and gameplay that emphasizes the immense but fleeting power that the Void offers . Mind Blast , , and Vampiric Touch will build Insanity . Reaching maximum Insanity will transform Shadowform into Voidform , giving the shadow priest access to stronger Void magic , but it is unable to be maintained indefinitely . This should make for interesting gameplay as shadow priests try to maintain the height of their Insanity as long as possible to prey on the minds of their enemies . While not under the effects of Insanity , shadow priests continue to rely heavily on abilities that inflict sustained damage over time . Finally , having turned away from the Light , shadow priests eschew such spells as Heal , Flash Heal , and Prayer of Mending . and Shadow Mend are their primary healing tools . Additionally , to give you an idea of how some talents may build upon this , here ’ s an example of one of their Shadow - specific talents : Discipline . The power of absorption mechanics has created a gameplay issue for healers that we ’ re looking to address in Legion . Discipline priests have been so effective in their role of preventing damage that it has sometimes left other healers yearning for an opportune time to throw out a clutch heal . To alleviate that issue , we ’ re tempering discipline ’ s emphasis on shields in lieu of a reimagined Atonement mechanic . Discipline priests are now more clearly defined by their use of both Holy and Shadow magic , and that extends to how they function in combat . Sacrificing a portion of healing ability and having a reduced focus on absorption spells , they gain a significant contribution in damage . Still filling a healer role in group content , they aim to strike a balance between healing allies and damaging enemies in a unique gameplay style . Discipline priests have strong cooldowns with and Pain Suppression , along with Rapture , a new cooldown that temporarily removes the cooldown of . Here ’ s a basic look at the core defensive and offensive combat abilities for Discipline Priests : Additionally , to give you an idea of how some talents may build upon this , here ’ s an example of one of their Discipline - specific talents :