If, by "ability" you mean "skill", and by "target", you mean "Ally", then take a look at the Blink skill, which sets the Blink state, which raises the evade by 100. (change to meet your needs, or create a new skill/state using Blink as an example.)
Be Well
P.S. easy on that 'pro' stuff.
The only bonafide "pro" here is Lambchop (that I know of).