CausalXXLinkXx is a downloadable Ghost Duelist in Yu-Gi-Oh! 5D's World Championship 2009: Stardust Accelerator.
She is a character created and used by the third place participant of the Stardust Accelerator World Championship tournament, who identifies as a male player named Matthew Johnson. Flower and Ayu were first and second place respectively in the tournament.
CausalXXLinkXx uses a DARK Synchro Deck, which was used by her creator in the World Championship tournament. It is titled "3rd Place Deck" within the video game, but at the World Championship Tournament it was called "KennySo.dek".