Essencecombinations #
You can mount up to 3 essences in your items. This is the list of all possible essence combinations.
Two Essences #
If you combine two essences you get additional attributes.

Agility
Gives Increased Movement Speed: 10%Combination:

Ambition
Gives Increased Critical Damage: 15%Combination:

Continuity
Gives Increased Buff/Pet/Ae Lifetime: 25%Combination:

Determination
Gives Increased Damage Done: 8%Combination:

Endurance
Gives Reduced Normal Damage Taken: 6%Combination:

Enthusiasm
Gives Reduced Ability Cooldown: 10%Combination:

Regeneration
Gives Increased Regeneration: 15%Combination:

Resistance
Gives Reduced Magic Damage Taken: 9%Combination:

Resourcefulness
Gives Decreased Resource Consumption: 15%Combination:

Restoration
Gives Increased Healing Done: 10%Combination:
Three Essences #
If you combine three essences you get certain effects. Every weapon has their own essence combinations. Here is a list of all combinations for armors and trinkets.

Bottled Demon
Your abilities have the chance to fire a bolt at your current targetCombination:

Combat Conditioning
If you drop below 45% health get 15 awareness increase, 45s cooldownCombination:

Invigoration
Every ability can trigger Invigoration granting 5 spirit to the whole raidCombination:

Lethality
After 2 critical ability hits gain critical damageCombination:

Spirit of the Sea
Every 4s heal the lowest ally in the raid, for: Pwr*5+20Combination:

Steamroller
You get a stack every time you take damage, 20 stacks grant you 5 Pwr and 10 StaCombination: