Rating

Introduced in the Gears of Change event, Rating is a modifier to incoming and outgoing damage, healing, mana consumption, mana charging, and aetheria surging.

Listed below is a brief description of all the known types of rating along with links to articles that include ways to increase/decrease them.

Damage

Damage rating increases all damage done to a target, including critical hits.

Formula: (100 + <total damage rating>)/100 = 1.xx modifier to damage

Spell: Damage (Spell)

Name	Rating	Max Rating	Duration	Obtained From
Augmented Damage	+1 Damage Rating	+3 Damage Rating	Item	Item Tinkering
Aura of Destruction	+1 Damage Rating	+5 Damage Rating	Innate	Luminance
Aura of Valor	+1 Damage Rating	+5 Damage Rating	Innate	Luminance
Frenzy of the Slayer	+3 Damage Rating	+3 Damage Rating	Innate	Augmentation Gems
Rare Armor Damage Boost	+5 Damage Rating	+5 Damage Rating	Item	Luminance Gems
Rare Damage Boost	+1 Damage Rating	+10 Damage Rating	Item	Rares
Sigil of Destruction*	+1 Damage Rating	+9 Damage Rating	Item	Aetheria
Weapon Mastery	+5 Damage Rating	+5 Damage Rating	Innate	Weapon Mastery
Surge of Destruction	+20 Damage Rating	+20 Damage Rating	10 Seconds	Aetheria
Surging Strength	+20 Damage Rating	+20 Damage Rating	15 Seconds	Luminance Gems
Recklessness	+10 Damage Rating	+20 Damage Rating	When Active	Recklessness
Sneak Attack	+10 Damage Rating	+20 Damage Rating	When Active	Sneak Attack
??	+1 Damage Rating per item +3 for all (shirt, pants, cloak)	+2 Damage Rating per item +6 for all (shirt, pants, cloak)	Item	Loot (tier 8)
Max Possible		+131 Damage Rating
Max Base (with Rare weapon)		+46 Damage Rating

Note: Total possible includes consumable items, and surges.
*Sigil of Destruction may go to +10 with 3 level 5 Destruction aetheria, but it remains untested.

Critical Damage

Critical Damage Rating increases Critical Hit damage done to a target.

Formula: (100 + <total critical damage rating>)/100 = 1.xx modifier to critical damage

Name	Rating	Max Rating	Duration	Obtained From
Aura of Glory	+1 Critical Damage Rating	+5 Critical Damage Rating	Innate	Luminance
Aura of Retribution	+1 Critical Damage Rating	+5 Critical Damage Rating	Innate	Luminance
Hand of the Remorseless	+3 Critical Damage Rating	N/A	Innate	Augmentation Gems
Sigil of Fury*	+1 Critical Damage Rating	+9 Critical Damage Rating	Item	Aetheria
??	+1 Critical Damage Rating per armor piece +9 for all	+2 Critical Damage Rating per armor piece +18 for all	Item	Loot (tier 8)
Total Possible		+40 Critical Damage Rating

*Sigil of Fury may go to +10 with 3 level 5 Fury aetheria, but it remains untested.

Damage Resistance

Damage Resistance Rating decreases the amount of all incoming damage, including critical hits.

Formula: 100/(100 + <total damage resistance rating>) = .xxx modifier to incoming damage.

Name	Rating	Max Rating	Duration	Obtained From
Augmented Damage Reduction	+1 Damage Resistance Rating	+3 Damage Resistance Rating	Item	Item Tinkering
Aura of Invulnerability	+1 Damage Resistance Rating	+5 Damage Resistance Rating	Innate	Luminance Aura
Aura of Protection	+1 Damage Resistance Rating	+5 Damage Resistance Rating	Innate	Luminance Aura
Iron Skin of the Invincible	+3 Damage Resistance Rating	N/A	Innate	Augmentation Gems
Rare Damage Reduction	+1 Damage Resistance Rating	+5 Damage Resistance Rating	Item	Rares or Luminance Gem
Sigil of Defense*	+1 Damage Resistance Rating	+9 Damage Resistance Rating	Item	Aetheria
Surge of Protection	+20 Damage Resistance Rating	N/A	10 Seconds	Aetheria
Towering Defense	+20 Damage Resistance Rating	N/A	15 Seconds	Luminance Gem
??	+1 Damage Resistance Rating per item +3 for all (shirt, pants, cloak)	+3 Damage Resistance Rating per item +9 for all (shirt, pants, cloak)	Item	Loot (tier 8)
Max Possible		+84 Damage Resistance Rating
Max Base (with Rare Armor)		+44 Damage Resistance Rating

Note: Total possible includes consumable items, and surges.
*Sigil of Protection may go to +10 with 3 level 5 Defense aetheria, but it remains untested.

Critical Damage Resistance

Critical Damage Resistance Rating decreases Critical Hit damage received.

Formula: 100/(100 + <total critical damage resistance rating>) = .xxx modifier to critical hit damage received.

Name	Rating	Max Rating	Duration	Obtained From
Aura of Hardening	+1 Critical Damage Resistance Rating	+5 Critical Damage Resistance Rating	Innate	Luminance
Aura of Temperance	+1 Critical Damage Resistance Rating	+5 Critical Damage Resistance Rating	Innate	Luminance
??	+1 Critical Damage Resistance Rating per armor piece +9 for all	+2 Critical Damage Resistance Rating per armor piece +18 for all	Item	Loot (tier 8)
Total Possible		+28 Critical Damage Resistance Rating

Damage over Time Resistance

Decreases the effectiveness of Damage Over Time spells cast upon the user

Formula: 100/(100 + <total DoT Reduction Rating>) = .xxx modifier to outgoing incoming damage over time attacks.

Name	Rating	Max Rating	Duration	Cast By
Sigil of Purity	4 DoT Reduction Rating	36 DoT Reduction Rating	Innate	Aetheria

Sigil of Purity may go to +40 with 3 level 5 Growth aetheria, but it remains untested.

Health Drain Resistance

Decreases the effect of drain spells cast upon the target.

Formula: 100/(100 + <total health drain resistance rating>) = .xxx modifier to incoming health drains.

Name	Rating	Max Rating	Duration	Cast By
Sigil of Perserverance	4 Health Drain Resistance Rating	36 Health Drain Resistance Rating	Innate	Aetheria
Total Possible		36 Health Drain Resistance Rating

Sigil of Perseverence may go to +40 with 3 level 5 Vigor aetheria, but it remains untested.

Healing Boost

Healing Boost Rating increases the amount of health received from consumables, healing kits, and life magic.

Formula: (100 + <total healing rating>)/100 = 1.xx modifier to healing.

Name	Rating	Max Rating	Duration	Obtained From
Aura of Purity	+1 Healing Boost Rating	+5 Healing Boost Rating	Innate	Luminance
Sigil of Growth*	+1 Healing Boost Rating	+9 Healing Boost Rating	Item	Aetheria
??	+1 Healing Boost Rating per item +6 for all (bracelets, rings, necklace, trinket)	+3 Healing Boost Rating per item +18 for all (bracelets, rings, necklace, trinket)	Item	Loot (tier 8)
Total Possible		+32 Healing Boost Rating

*Sigil of Growth may go to +10 with 3 level 5 Growth aetheria, but it remains untested.

Aetheria Surge

Increases the chance that Aetheria will surge.

Formula:(100 + <Aetheria Surge Rating>)/100 = 1.xx modifier to Aetheria Surges.

Name	Rating	Max Rating	Duration	Obtained From
Aura of Aetheric Vision	+1 Aetheria Surge Rating	+5 Aetheria Surge Rating	Innate	Luminance

Mana Charge

Increases the amount of mana released from mana stones into magical items.

Formula:(100 + <Mana Charge Rating>)/100 = 1.xx modifier to Mana Charges.

Name	Rating	Max Rating	Duration	Obtained From
Aura of Mana Infusion	+5 Mana Charge Rating	+25 Mana Charge Rating	Innate	Luminance

Mana Reduction

Decreases the amount of mana consumed in equipped magical items.

Formula: Mana Usage = 100/(100 + Mana Reduction Rating)

Name	Rating	Max Rating	Duration	Obtained From
Aura of Mana Flow	+5 Mana Reduction Rating	+25 Mana Reduction Rating	Innate	Luminance

Damage Reduction

Debuff applied to decrease the effective damage rating of the target.

Formula: 100/(100 + <total damage rating debuff>) = .xxx modifier to outgoing damage.

Name	Rating	Max Rating	Duration	Cast By
Weakening Curse	-1 Damage Rating	-15 Damage Rating	15 Seconds	Void Magic

Healing Reduction

Debuff applied to decrease the effective healing rating of the target.

Formula: 100/(100 + <total healing reduction rating>) = .xxx modifier to healing.

Name	Rating	Max Rating	Duration	Cast By
Festering Curse	10 Healing Reduction Rating	45 Healing Reduction Rating	30 Seconds	Void Magic
Curse of the Burning Sands	25 Healing Reduction Rating	N/A	5 Minutes	Burning Sands Golem
Surge of Festering	20 Healing Reduction Rating	N/A	20 Seconds	Aetheria
Traumatic Blow	15 Healing Reduction Rating	N/A	20 Seconds	Dirty Fighting
Traumatic Assault	30 Healing Reduction Rating	N/A	20 Seconds	Dirty Fighting
Total Possible		95 Healing Reduction Rating

Note: Total possible includes aetheria surge, but not creature casted.

Damage Resistance Reduction

Debuff applied to decrease the effective damage resistance rating of the target.

Formula: 100/(100 + <total damage resistance reduction rating debuff>) = .xxx modifier to incoming damage.

Name	Rating	Max Rating	Duration	Cast By
Recklessness	-10 Damage Resistance Rating	-20 Damage Resistance Rating	When Active	Recklessness

Notes

See Severlin's post on the official forums for more information [1], [2], [3], [4], [5] .
At this time, all increases to any rating stack with each other.