Resistance
Resistances reduce the damage you take from their associated element. Enemies can also have resistances, which are indicated beneath their life bar.
Each elemental damage type has it's own resistance value (e.g. "Fire resistance") which is viewable in the character sheet. The maximum value for resistances is 75%, however some Unique items can increase your maximum resistances, as well as the aura Purity, and a passive skill located near the Marauder called Elemental Adaptation. Additionally, resistances can even become negative through the use of curses or by wearing Unique items that lower your resistance. Resistances are available on equipment, through passive skills, as a temporary buff from a flask, and from Endurance Charges (5% per charge). The "+% to All Resistances" stat grants resistance to all elements except Chaos. Chaos resistance can only be obtained through specific Unique items or the Chaos Inoculation keystone passive skill.
Resistance Penalties
There is a penalty of -20% to All Resistances applied to your character in each successive difficulty you reach. Again, this does not include Chaos damage.
- Normal: No penalty
- Cruel: -20% to All Resistances
- Ruthless: -40% to All Resistances
- Merciless: -60% to All Resistances
Resistance Penetration Mechanics
Some curses lower the resistances of their target. These curses are:
- Elemental Weakness: -% to All Resistances
- Conductivity: -% to Lightning Resistance
- Flammability: -% to Fire Resistance
- Frostbite: -% to Cold Resistance
These curses will reduced the target's resistance. If a monster has 75% resistance and is affected by a -40% resistance curse it will have 35% resistance. If a monster has 120% resistance (by way of auras or rare monster affixes), it will be capped at 75%, and upon being hit with a -40% curse, it will be reduced to 80% resistance and still be at the 75% cap.
Some support gems will cause supported skills to ignore a portion of target resistance. These are:
- Lightning Penetration: Ignores % of Lightning Resistance
- Fire Penetration: Ignores % of Fire Resistance
- Cold Penetration: Ignores % of Cold Resistance
These support gems reduced the actual resistance of a monster, or the resistance that a monster has at the point of damage. If a monster has 75% resistance and is affected by a 40% penetration support gem it will have 35% resistance, as with a curse. If a monster has 120% resistance, it will be capped at 75%, and for the purpose of the penetration support gems, its resistance will be 75%, not 120%. So a 40% penetration gem will reduce the resistance to 35% (which differs from the effect of curses). [1]