Vine

Vine is the Dekn Lord of Time, Cards, and Souls. He is the supposed force possessing Riley Sturza, he makes an appearance in MyDarkestSecret, and is a minor character in MedBoy789.

Riley Sturza
He is presumably the force possessing Riley in the Ante Up video, which is a black and white video of Riley with a demonic voice shuffling around cards while The Aces of Spades by Motorhead is playing in the background.

MyDarkestSecret
While Elliot is filming his sleep log at Riley's house, Riley gets up and shows a card to the camera at one point. Elliot later states in one of his videos that Riley has been acting weird.

MedBoy789
When Tobias Kestler is trapped in the Infernous, Vine shows up via video interface through Tobias' technologically enhanced phone and makes his formal introduction. He states that he is somewhat of a tour guide to the Infernous and tells Tobias that it was made by The Carver, who is now trapped in it. He also explains that his vessel, Riley, is a .Reality clone of him, and that if he has any questions about that, he can take it up with Persophelus Redgrave. Vine uses Riley's deck of Yu-Gi-Oh! cards to tell Tobias what is in store for him within the Infernous. He laughingly states that Tobias is to be faced with Peacocks, a javelin, and being buried alive before making his departure.