In Path of Exile, the Power of Purpose Keystone is a unique passive skill that offers a conversion mechanic, allowing players to trade a percentage of their maximum mana for double that amount in armor. While it may not be as popular as other Timeless Keystone options, the Power of Purpose Keystone can provide a significant defensive boost during the early game and has specific use cases that make it valuable for certain character builds. In this guide, we will delve into the mechanics, interactions, and potential applications of the Power of Purpose Keystone.

• About Power of Purpose Keystone
• Acquiring the Power of Purpose Keystone
• Mechanics of the Power of Purpose Keystone
• Example of the Conversion Mechanic
• Interaction with Increases to Maximum Mana and Armor
• Interaction with Modifiers that Grant Extra Maximum Energy Shield
• Hierophant Build Synergy
• Early Game Utility and Future Potential

↖ About Power of Purpose Keystone

The Power of Purpose Keystone is a unique keystone passive skill in Path of Exile that offers a conversion mechanic, allowing players to convert mana into armor. This keystone can be acquired by socketing a Militant Faith unique Timeless Jewel into the passive skill tree, which replaces and overrides any other keystones within its radius. The Militant Faith jewel must have the specific modifier "Carved to glorify (2000-10000) new faithful converted by High Templar Avarius" to grant the Power of Purpose Keystone.

It's important to note that the Timeless Jewel only affects regular keystones and does not impact cluster jewel keystones. To activate the Power of Purpose Keystone, players need to allocate it on the passive skill tree directly. It cannot be allocated using unique items like Skin of the Lords. However, unique items that allocate the original keystone can be used in conjunction with the Timeless Jewel keystone, allowing players to benefit from unique combination effects.

Alternatively, players can place the Timeless Jewel in another jewel socket on the passive skill tree, conquering a different part of the skill tree that doesn't contain the essential build-enabling keystones. This way, they can utilize the Power of Purpose Keystone while still benefiting from their desired keystone combinations elsewhere on the tree.

↖ Acquiring the Power of Purpose Keystone

To obtain the Power of Purpose Keystone, players need to socket a Timeless Jewel called the Militant Faith into their passive skill tree. The name of the jewel must include Power of Purpose, and it is the only source for acquiring this Keystone. As a Timeless Keystone, it competes directly with other powerful Timeless Keystone passives.

↖ Mechanics of the Power of Purpose Keystone

The Power of Purpose Keystone offers a single modifier: 80% of maximum mana is converted into twice that amount of armor. This conversion mechanic is a rare attribute outside of damage conversion mechanics. Unlike reservation mechanics, Power of Purpose allows players to continue reserving a portion of their mana pool for auras and other skills. This distinction becomes important when considering the use of flat mana auras versus percentage-based auras and reservation skills.

↖ Example of the Conversion Mechanic

Let's consider an example to understand how the conversion mechanic of Power of Purpose works. Suppose a character has a maximum mana of 600 and allocates the Power of Purpose Keystone. Their mana pool would be reduced to 120, and they would gain 960 flat armor (twice the amount of lost mana). This example highlights the trade-off between mana and armor when utilizing Power of Purpose.

↖ Interaction with Increases to Maximum Mana and Armor

Increases to maximum mana will directly increase the armor gained through the Power of Purpose Keystone. For instance, if the same character with 600 mana allocates modifiers that grant a total of 50% increased maximum mana, their maximum mana would become 900. With the Power of Purpose Keystone, their mana pool would be reduced to 180, resulting in 1440 armor from the Keystone. Additionally, any increases to maximum mana will only affect the armor granted by the Keystone, while increases to armor will improve armor from other sources such as gear or auras.

↖ Interaction with Modifiers that Grant Extra Maximum Energy Shield

When Power of Purpose is combined with modifiers that grant extra maximum energy shield based on maximum mana, such as the Hierophant's Sanctuary of Thought notable, the interaction becomes more complex. Increases to maximum mana will affect both the armor granted by Power of Purpose and the energy shield granted by modifiers. The total extra energy shield gained is determined by the original mana value prior to conversion.

↖ Hierophant Build Synergy

One of the strongest use cases for the Power of Purpose Keystone is with the Hierophant ascendancy class, specifically when combined with Sanctuary of Thought. Hierophants can benefit from the increased mana reservation efficiency granted by Sanctuary of Thought and use their entire mana pool to reserve powerful auras and skills. By utilizing Mind over Matter, Eldritch Battery, and energy shield leech mechanics, Hierophants can effectively use energy shield as a resource for mana skills, while still maintaining energy shield as a defensive barrier.

↖ Early Game Utility and Future Potential

For characters located on the top or right side of the passive skill tree, Power of Purpose can serve as a valuable early game Timeless Keystone. It provides much-needed physical damage mitigation during early map progression. As players acquire stronger gear and other upgrades, they may choose to swap out Power of Purpose for more potent Keystone options in the late game. However, it's worth noting that the utility of Power of Purpose may increase if access to it is added through other sources, such as unique items.

Conclusion:

The Power of Purpose Keystone in Path of Exile offers a unique conversion mechanic that trades a percentage of maximum mana for double that amount in armor. While it may not be widely popular due to its limited availability, it provides a significant defensive boost during early game progression and can synergize well with specific character builds, particularly those utilizing the Hierophant ascendancy class. Keep an eye out for future developments that may expand the usefulness of Power of Purpose. Stay tuned for more guides like this in the future. Thank you for reading, and remember to like, subscribe, and support the channel for more Path of Exile content. Stay safe and happy hunting!