The maximum Chaos Resistance you can achieve in Path of Exile depends on two factors:
Base Maximum Chaos Resistance:
This is a soft cap set at 75%, similar to other elemental resistances. This means you can reach 75% Chaos Resistance through standard means like gear, passives, and auras.
Increased Maximum Chaos Resistance:
Certain sources can increase your maximum Chaos Resistance beyond the 75% cap. These are relatively rare and often require specific investments:
Keystone Passive Skills:Chaos Inoculation grants complete immunity to Chaos Damage but disables Energy Shield and regeneration. This effectively pushes your maximum Chaos Resistance to 100%.
Unique Jewels: A few unique jewels like "The Formless Void" offer a flat increase to your maximum Chaos Resistance.
Corrupted Items: Rare corrupted items (primarily body armor) can have the implicit modifier "+(x)% to maximum Chaos Resistance."
Synthesis implicits: Specific Amulets with Synthesis implicits can offer increased maximum Chaos Resistance.
Important Notes:
Diminishing Returns: While exceeding the 75% cap is possible, the benefit of each additional point of Chaos Resistance diminishes significantly after a certain point. Consider other defensive layers in conjunction with high Chaos Resistance.
Investment Cost: Reaching extremely high Chaos Resistance often requires rare and expensive items or specific build choices. Weigh the cost-benefit carefully.
Chaos Damage Over Time: Unlike elemental damage, Chaos Damage Over Time effects (e.g., Degeneration) cannot be completely negated by high Chaos Resistance. You still need recovery mechanisms to mitigate them.
Who might benefit from exceeding 75% max Chaos Resistance:
Characters focusing on Chaos Inoculation: This keystone makes maximizing Chaos Resistance crucial for survival.
Builds facing heavy Chaos Damage: Some endgame content and specific encounters primarily deal Chaos Damage, justifying high Chaos Resistance investment.
Alternatives to High Chaos Resistance:
Chaos Damage Reduction: Certain skills and items offer direct Chaos Damage Reduction, which can be effective alongside moderate Chaos Resistance.
Recovery Mechanisms: High life pool, Energy Shield regeneration, and effective use of flasks are crucial for surviving Chaos Damage Over Time effects.
Ultimately, the decision of whether or not to aim for high Chaos Resistance depends on your build, playstyle, and the challenges you encounter. Weigh the pros and cons of different defensive strategies to find the best approach for your character.