"New" Abilities?

I want to re-add the "Beserk" ability of Headhunters from the beta.

Where, when in Beserk the Headhunters would do twice the amount of damage to enemies, and take twice as much in return.

Is there a way to do this via an Ability Editor or such? So far all I've seen is modifying already exsisting abilities in the game, which sorta puts a limit on the creativity... :(

See hwta you can do with Faraie Fire or Inner Fire, as they modify armor and damage so you might be able to do somehting there. You might have to make an ability like mirror image that does nothing, and use triggers to do what you want.