Mechanic

Efficiency

Efficiency reduces a cost or reservation by dividing its base amount. Increased Efficiency has diminishing returns: 50% increased Efficiency divides by 1.5, while 100% increased Efficiency divides by 2. It is not the same calculation as reduced cost or less reservation.

0.5.4d

Current data

Catalog version 0.5.4d

No direct 0.5 patch change is linked to this page. The displayed values are current for catalog version 0.5.4d.

What Efficiency does

Current rules

Use final amount = modified base amount / (1 + total increased Efficiency / 100), then round the reservation up to a whole resource point when necessary. A 60 Spirit reservation becomes 40 with 50% increased Reservation Efficiency and 30 with 100%. A 100 Spirit reservation becomes 80 with 25%, 67 with 50%, and 50 with 100%.

Efficiency is a divisor: Add all applicable increased and reduced Efficiency modifiers, convert the total to a multiplier around the baseline of 1, and divide the modified base amount by that value.
The general formula: Final amount = modified base amount / (1 + total increased Efficiency / 100). For 50% increased Efficiency, divide by 1.5. For 100%, divide by 2. For 200%, divide by 3.
Reservation rounds to whole points: Fractional reservations are rounded up in the displayed result. A base reservation of 30 with 75% increased Reservation Efficiency is 30 / 1.75 = 17.14, which reserves 18 Spirit.
Increased Efficiency has diminishing returns: The first 100% increased Efficiency halves the amount, but another 100 percentage points changes it from one half to one third rather than to zero. Efficiency therefore cannot reach a free reservation merely by stacking ordinary increased Efficiency.
Reduced Efficiency makes the amount larger: Reduced Efficiency lowers the divisor. At 50% reduced Efficiency, the divisor is 0.5 and a 30 Spirit reservation becomes 60. At 100% reduced Efficiency, the divisor reaches zero and the affected reservation cannot be enabled.
More and less Efficiency are multiplicative: More or less Reservation Efficiency modifies the efficiency value multiplicatively rather than adding to increased or reduced Efficiency. A separate less Reservation modifier instead multiplies the reservation amount after the efficiency calculation.
Cost and reservation scopes remain separate: Cost Efficiency affects Skill costs. Reservation Efficiency affects reservation. A modifier may also be limited to Spirit, a Skill tag, a Skill family, or a specific Skill, so the same percentage does not necessarily apply to every action.

Worked Reservation Efficiency examples

6 cases

30 Spirit base

0% reserves 30, 25% reserves 24, 50% reserves 20, 75% reserves 18, 100% reserves 15, 150% reserves 12, and 200% reserves 10.

Related: Reservation, Spirit

60 Spirit base

0% reserves 60, 25% reserves 48, 50% reserves 40, 75% reserves 35, 100% reserves 30, 150% reserves 24, and 200% reserves 20.

Related: Reservation, Spirit

100 Spirit base

0% reserves 100, 25% reserves 80, 50% reserves 67, 75% reserves 58, 100% reserves 50, 150% reserves 40, and 200% reserves 34.

Related: Reservation, Spirit

Scoped unique items

Prism Guardian scales Buff Skill reservation with maximum Life, Bones of Ullr applies to Undead Minion Skills, The Hollow Mask applies to Remnant Skills, and The Raven's Flock applies to Skills generally.

Block chance25%Armour(280-336)Energy Shield(77-93)Base Movement Speed-0.015RequiresLevel 65, 50 Str, 50 IntGrants Skill: Raise Shield (Level 25)(150-200)% increased Armour and Energy Shield+50 to Spirit+(20-30) to Dexterity+(10-20)% to all Elemental Resistances1% increased Spirit Reservation Efficiency of Buff Skills per 100 Maximum LifeWhen blood is paid, the weak think twice., Bones of Ullr, The Hollow MaskThe Hollow MaskUnique | Hewn Mask

Evasion Rating20Energy Shield13RequiresLevel 5, 7 Dex, 7 IntGrants Skill: Wildwood's Gifts (Level 3)+(60-80) to maximum Life15% additional Physical Damage Reduction-10% to all Elemental Resistances+13% to Chaos ResistanceRemnants you create affect Allies in your Presence as well as you when collected(80-100)% increased Reservation Efficiency of Remnant SkillsThe roots burrow deeper, unveiling the wood's bounty..., The Raven's FlockThe Raven's FlockUnique | Perching Staff

RequiresLevel 65, 114 IntGrants Skill: Spiraling Conspiracy (Level 19)(8-16)% increased Cast Speed+(20-30) to IntelligenceMinions deal (80-120)% increased DamageMinions have (10-20)% chance to inflict Gruelling Madness on Hit(30-50)% increased Spirit Reservation Efficiency of Skills"Where the boy went, ravens gathered,feasting on misery. His vile influencespread, swift as the carnage they wrought."

Positive equipment sources

Rune of the Blossom grants generic Spirit Reservation Efficiency of Skills, Greater Rune of Alacrity grants Herald Reservation Efficiency, and Bear Idol grants Companion Reservation Efficiency when used in their stated equipment slots.

Currency: Rune of the Blossom, Greater Rune of Alacrity, Bear Idol

Negative Efficiency

Idol of the Martyr and Idol of the Pharisee can impose reduced Reservation Efficiency on their stated targets. Reduced Efficiency increases the final reservation instead of decreasing it.

Currency: Idol of the MartyrIdol of the MartyrNormal | Idol

Stack Size1 / 10Limited to1RequiresLevel 50Martial Weapon, Wand or Staff: 25% reduced Spirit, Meta Skills gain 40% increased EnergySceptres: 40% reduced Presence Area of Effect, Aura Skills have 25% increased MagnitudesMartial Weapon, Wand or Staff: Invocated skills have 25% increased Maximum Energy, Meta Skills have 25% reduced Reservation EfficiencySceptres: Allies in your Presence Regenerate 3% of your Maximum Life per second, 25% reduced Life Regeneration rate, Idol of the PhariseeIdol of the PhariseeNormal | Idol

Stack Size1 / 10Limited to1RequiresLevel 50Martial Weapon, Wand or Staff: 30% reduced maximum Mana, Gain 2% of Damage as Extra Physical Damage per ten percent missing ManaSceptres: 30% reduced Mana Cost Efficiency of Command Skills, Minions deal 60% increased Damage with Command SkillsMartial Weapon, Wand or Staff: 30% reduced Mana Cost Efficiency, 12% increased Skill Speed while on Low ManaSceptres: 25% reduced Reservation Efficiency of Minion Skills, Temporary Minion Skills have +2 to Limit of Minions summoned

Limits and exceptions

5 rules

Do not subtract an Efficiency percentage directly from the base amount.
Do not combine increased Efficiency and less reservation as if they were the same modifier.
Round the final reservation according to the game's whole-resource display.
Only modifiers whose resource and Skill scope match the reservation are included.
Reduced Efficiency can make a reservation larger or impossible to enable.

Related mechanics

MechanicReservation

Reservation commits part of a resource to an active effect. Most persistent Skills reserve Spirit, but some effects reserve Life or Mana. The reserved amount remains part of the resource's maximum and cannot be spent, recovered, or used as defence while it is reserved.