>do you mean beyond the standard R1 and R2 strings? i
>understand that the weapon can transform mid-string. do
>weapons have attacks that are unique to mid-string
>transformations?

Yup.

So, the basics aren't much different from DS —

R1: Light Melee
R2: Heavy Melee
L1: Transform
L2: Off-hand Attack (Gunshot or whatever)
Square: Item / Magic

You then have a charge attack by holding down R2 for various durations.

Most weapons have 2 transform attacks for use in strings, though I think some (like the Reiterpallasch) have 3 and two of them are... weird.

So, like the Saw Spear has a really great combo of starting in Spear form, back step R1 for overhead slam > transform to closed for quick doubleslash > transform back to extension for left to right swipe > R2 for thrust > L2 to try for a stagger.