For new attacks like the Cleave weapon mastery, the attack is made without adding your Ability Bonus to the damage.  It would be really nice (for speed and convenience in gameplay) if I could create a custom attack that didn't have the stat modifier.  Right now, with the options presented for Custom Actions, I don't see any way to get the stat bonus out of there.  

If there's already a way to add this attack or to generate a Cleave without the bonus, please let me know how to set that up.

It's a small thing, but if it's easy to fix I would appreciate it.  Thanks!

Loquitur

I'm not sure if you can or not as a custom attack and can't be bothered to faff around to just find out if there's a way.

I do know it is possible to make a spell that'll do it, and then make a feat to add the spell, using the relevant attack ability, to the character. This way it'll have the correct attack roll and damage without ability modifier.