Every major Mario character's Dark Souls build:
Mario: Quality build - very straightforward straight sword and shield
Luigi: Dexterity build - probably a rapier and a big shield to hide behind
Wario: Miracles/Intelligence hybrid
Waluigi: Pyromancy and a polearm
Bowser: Big Strength sword and Pyromancy
Peach: Levels up every stat equally :) - probably uses a whip or something because the animations are pretty
Daisy: Dual wielding Pyromancy Flames (let the world burn)
Rosalina: Sorcery, very minmaxed Intelligence build
Yoshi: Dual wielding bone wheel shield :)