Evasion

Evading an attack prevents all damage and other harmful effects from the attack. Only attacks and attack skills can be evaded. Spells cannot normally be evaded, but the Phase Acrobatics keystone ability gives a 20% chance to dodge spells.

Mechanics

Your chance to evade an attack is based on the attacker's accuracy and your evasion.
Chance to evade = 1 - Attacker's Accuracy / (Attacker's Accuracy + (Defender's Evasion/4)^0.8)