attack that does exact HP's worth of damage in DBS? (2k3)

[orewashinanai]

Hi all,

This is my first time posting (please let me know if this question's already answered somewhere else).  I want to create an attack that does an exact amount of HP damage.  Is there an easy way to do this via the DBS? Do I have to manipulate stats and turn the variance to 0 so that an attack with do X amount of HP damage, or can I create a skill that, if successful, will do the same thing? Or is this completely hopeless and I have to resort to building an entire CBS?

Thanks for any help you can provide!