Robin uses Tekkai by MSJPSakura on DeviantArt

Is Rokushiki a fighting style? If it is, does Luffy use it? - Quora

Why didn't Luffy learn Rokushiki techniques? - Quora

Rokushiki Combos, How to Get, and Pros and Cons Gpo

World of Shinjoin! — The Nico Robin: Rokushiki style Project! (part2)

Rokushiki, Rob Lucci (One Piece)

Shigan, One Piece Role-Play Wiki

Rokushiki/Tekkai, OnePiece Fanon Wiki

Tekkai, One Piece Role-Play Wiki

Inu Inu no Mi, Model: Wolf in One Piece

Rokushiki is based on physical strength is actually based on a mistranslation in earlier One Piece volumes : r/OnePiece