++ Evasion
Pokemon have three different sets of Evasion. Physical Evasion, Special Evasion, and Speed Evasion.  Evasion helps Pokemon avoid being hit by moves. When being targetted by a move that has an Accuracy Check, a Pokemon adds their Evasion score to the move's accuracy check. Physical Evasion may modify only attacks that use the attack stat, while Special Evasion may modify only attacks that use the Special Attack Stat.  Speed Evasion may be used to modifythe Accuracy Check of any attack, but you may only add one of your three evasions to any one check.

Physical and Special Evasion are determined by a Pokemon's Defense and Special Defense Stats respectively. For every 5 points they have in the relevant defense stat,  that evasion is increased by +1, up to a maximum of +6.

Speed Evasion is determined by a Pokemon's Speed Stat. For every 10 points they have in Speed, their evasion is increased by +1, up to a maximum of +6.

Besides these base values for evasion, many other things can modify Evasion.  Raising your Defense, Special Defense, and Speed Combat Stages raises the relevant Evasion by +1. You do not gain further benefits from the artificially increased defense score, however.

 Abilities and Move Effects that modify your Evasion do so for all three of your evasion scores. For example, the Illuminate Ability helps you avoid all three kinds of attacks.

No matter from which sources you're receiving evasion, you may only ever raise a move's Accuracy Check by a maximum of +9.