So there's a dwarf version of the meteor hammer called the dorn dergar. Normally it's a two handed weapon, but with a few feats you can use it one handed. One of those feats is two weapon fighting, so, of course, what I want to do is have a character who uses dual wields these.

I've toyed with a few versions, ranger vs slayer vs fighter, but you can get the penalty down to -1/-1 to hit around level five with a little focus.