You can only use each effect of "Roxrose Dragon" once per turn
The simplest answer to this question is that cards that are not only desired but also rare enough to warrant a higher price from lack of supply are worth the most
The community has taken this desire for variety into its own hands by creating private match passwords that strongly encourage a specific playstyle, such as NOEX pairing you with other players not using the powerful EX cards that typically define the meta
Combined with other cards that add to your inkwell, such as Gramma Tala and Mickey Mouse, Detective, or other lore-generating cards, you could be in with a deck that barely gives your opponent a chance to know what hit them
The cheaper the card drawing, the more likely this is
Confused: A player indicates that a Pokmon is Confused by turning the card 180 degrees so that it is upside-down