Avoidance

.________________________________________________________________________.
| Item [Avoidance                     ]  Type [             Combat Skill]|
|________________________________________________________________________|
|______________________[        Description       ]______________________|
| Why absorb hits when you can just not take them? Increases your        |
| defense enhancing skills(like skitter) by 15/30/45%. Also allows you   |
| to roll with blows. You will resist up to 10/20/30% of an incoming     |
| attack, increasing as you are lower in hit points, starting at 3/6/9%. |
|________________________________________________________________________|
|______________________[       Available In       ]______________________|
| Assassin            [Damage,Speed,Avoidance                           ]|
| Buzzard             [Readiness,Avoidance,Scavenger                    ]|
| Emergency Doctor    [Healing,Avoidance,Speed                          ]|
| Fencer              [Tactician,Avoidance,Flurry                       ]|
| Judo Fighter        [Reactive,Accuracy,Avoidance                      ]|
| Messenger           [Avoidance,Speed,Endurance                        ]|
| Skirmisher          [Penetration,Avoidance,Front Row                  ]|
| Spy                 [Accuracy,Avoidance,Back Row                      ]|
| Survivor            [Endurance,Avoidance,Durability                   ]|
| Tri-Athlete         [Fast Loading,Avoidance,Endurance                 ]|
|________________________________________________________________________|

Feline Agility has a Defense effect of magnitude 10, so two ranks of Avoidance would increase that to 13.
The resistance effect seems to be percentage-based rather than the subtractive powers of armor.