Slow attacking art

Slow attacking art

ok i wanna know how to make a unit attack verrrrry slowly. and i dont meen by cooldown. (for ex.) let say i used a frost nove with 300% slow, it would make the target attack slowly. also have a higher cooldown but w/e. so how could i get that sort of effect without using a spell. Triggers would be ok 2. does it have to do with combat animation backswing point and combat animation damage point? if so tell me how to use it properly. i have no idea what it does

one easy solution would be endurance aura with negative benefits