The Helm of the Lord of Death.
MDEF +5
Increases physical damage inflicted on Boss monsters by 10%.
Increases damage taken from Normal monsters by 5%.

For every refine level above +5:
Increases physical damage inflicted on Boss monsters by 1%.

When combined with Abysmal Knight Card:
Increases physical damage inflicted on Boss monsters by 5%.
Refine Level +11:
Reduces damage taken from Normal monsters by 5%.

[iRO Description]
The Helm of the Lord of Death
MDEF + 5.
Increase Damage to Boss Type Monsters by 10%
Take 5% more damage from normal Monsters and Players.
For every upgrade 5 and higher add 1% more damage to Boss Class monsters.

Set Bonus
Lord of the Dead Helm
Abysmal Knight Card
Increase Damage to Boss Type Monster by additional 5%.
If Lord of the Dead Helm +11 negates the damage from normal Monsters and Players.
The Abysmal Knight Card effect is only effective once.
Location: Upper Middle
Defense: 10
Required Level: 70
Jobs: All

More Information on Combo:

• Shield Of Death[1] & Lord of the Dead Helm[1]