@Kabs12's Findings

The original spreadsheet can be found here.

The Diamond's Victory item set in The Elder Scrolls Online was overlooked by quite a lot of testers and theorycrafters until late into the Public Test Cycle for Blackwood otherwise known as Update 30.

The set bonuses at gold value include:

2x Pieces - Adds 129 Weapon Damage and Spell Damage

3x Pieces - Adds 657 Critical Chance

4x Pieces - Adds 129 Weapon Damage and Spell Damage

5x Pieces - While in combat, using an ability with a range of 7 meters or less grants you Range Supremacy for 5 seconds, adding 437 Weapon Damage and Spell Damage to your damage over time and ranged attacks. While in combat, using an ability with a range of over 7 meters grants you Melee Supremacy for 5 seconds, adding 437 Weapon Damage and Spell Damage to your melee attacks.

For classes such as Nightblade and Necromancer, the set could provide both Range and Melee Supremacy proc buffs at the same time rather than in rotation. For certain setups or skill lines such as Bow, Melee or Range Supremacy would be the sole proc by logic.

The amount of damage added by the set in conjunction with certain sets like Bahsei's Mania proves to be promising in applicable fights and instances.

Unless otherwise detailed, assume morphs work the same as their base skills. Note that Kabs' testing was done through the lens of PvE DPS not PvP or other PvE roles which is why certain skill lines or skills such as One Hander and Shield or Momentum are not included.

General Abilities

Ability/Skill
Melee Supremacy
Range Supremacy
Light Attack (Inferno)
YesNo
Light Attack (Dual Wield)
No
Yes
Light Attack (Bow)
YesNo
Light Attack (Two Handed)
NoYes
Bash
NoYes

Armor and World Skills

Ability/Skill
Melee Supremacy
Range Supremacy
Annulment
NoYes
Evasion
NoYes
Unstoppable
NoYes
Soul Trap
YesNo
Eviscerate (Vampire)
NoYes
Blood Frenzy (Vampire)
NoYes
Blood Scion (Vampire)
NoYes

Synergy Activation

Synergy
Melee Supremacy
Range Supremacy
Radiate (Inner Fire)
YesNo
Spawn Broodlings (Trapping Webs)
YesNo
Any Other Synergy
NoYes

Guild and Alliance War Skills

Ability/Skill
Melee Supremacy
Range Supremacy
Silver Bolts
YesNo
Circle of Protection
NoYes
Expert Hunter
NoYes
Trap Beast
No
Yes
DawnbreakerNo
Yes
MagelightNoYes
EntropyYesNo
Fire Rune
YesNo
Equilibrium
NoYes
Meteor
YesNo
Imbue Weapon
NoYes
AccelerateNoYes
Trapping Webs
YesNo
Necrotic Orb
NoYes
Magicka Detonation
YesNo
Proximity Detonation
No
Yes
CaltropsYesNo

Destruction Staff Skills

Ability/Skill
Melee SupremacyRange Supremacy
Force Shock
YesNo
Wall of Elements
NoYes
Destructive Touch
YesNo
Weakness of Elements
YesNo
ImpulseNoYes
Elemental Ring
YesNo
Elemental Rage
YesNo

Dual Wield Skills

Ability/SkillMelee SupremacyRange Supremacy
FlurryNoYes
Twin Slashes
NoYes
WhirlwindNoYes
Blade Cloak
NoYes
Hidden Blade
YesNo
LacerateNoYes

Two Handed Skills

Ability/SkillMelee SupremacyRange Supremacy
UppercutNoYes
Critical Charge
YesNo
CleaveNoYes
Reverse Slash
NoYes
Berserker Strike
NoYes

Necromancer Skills

Ability/SkillMelee SupremacyRange Supremacy
Ricochet Skull
YesNo
Stalking Blastbones
YesYes
BoneyardYesNo
Skeletal Mage
NoYes
SiphonYesNo
ColossusYesNo
Death Scythe
NoYes
Bitter Harvest
NoYes
Grave Grasp
NoYes
Spirit Mender
NoYes
Restoring Tether
YesNo

Warden Skills

Ability/SkillMelee SupremacyRange Supremacy
DiveYesNo
ScorchNoYes
SwarmYesNo
Betty Netch
NoYes
Falcon's Swiftness
NoYes
Feral Guardian
YesNo
Impaling Shard
NoYes
Winter's Revenge
YesNo

Dragonknight Skills

Ability/SkillMelee SupremacyRange Supremacy
Lava Whip
NoYes
Searing Strike
NoYes
Fiery Breath
NoYes
Fiery Grip
YesNo
InfernoNoYes
StandardNoYes
Dark Talons
NoYes
Inhale
NoYes
Ash Cloud
YesNo

Templar Skills

Ability/SkillMelee SupremacyRange Supremacy
Puncturing Strikes
NoYes
Spear Shards
YesNo
Radial Sweep
NoYes
Sun Fire
YesNo
Solar Barrage
NoYes
BacklashYesNo
Radiant Destruction
YesNo
Cleansing Ritual
NoYes

Sorcerer Skills

Ability/SkillMelee SupremacyRange Supremacy
Crystal Shard
YesNo
Crystal Weapon
NoYes
Dark Exchange
NoYes
Daedric Mines
NoYes
Daedric Tomb
YesNo
Negate Magic
YesNo
Unstable Familiar
NoYes
Daedric Curse
YesNo
Winged Twilight
NoYes
Conjured Ward
NoYes
Bound Armor
NoYes
Bound Armaments (2nd Cast)
YesNo
Storm Atronach
YesNo
Mages' Fury
YesNo
Lightning Form
NoYes
Lightning Splash
YesNo
OverloadNoYes

Nightblade Skills

Ability/SkillMelee SupremacyRange Supremacy
Assassin's Blade
NoYes
ImpaleYesNo
Teleport Strike
YesNo
BlurNoYes
Mark Target
YesNo
Grim Focus
NoYes
Grim Focus (2nd Cast)
YesNo
Death Stroke
NoYes
Veiled Strike
NoYes
Path of Darkness
NoYes
ShadeYesYes
StrifeYesNo
CrippleYesNo
Siphoning Attacks
NoYes
Drain Power
NoYes