Bash with a knockback.
Easiest way to just dl a Knockback system, which allows you to just use a single line of code to do all the knocking back for you.
Just need a trigger, to run when the Hero attacks, has the correct ability with a 15% to run the knockback.
That system should work if you implement it correctly. If I submit mine, I'd have to make a readme and a bunch of stuff before doing so. It wouldn't be released right away if anything.