When playing with double-faced cards, either the traditional transforming ones or their shiny new modal cousins, it's important to that your cards are indistinguishable from one another
Heck, many of the decks in Pioneer can be copied over one to one, and if there's something missing, there'll still be a version of the deck out there that has substitutes
However, it can always be kept around to teach younger siblings and cousins, or even adults who want to participate with their kids
With even just one dragon monster, Buster Blader's attack goes from an already strong 2600 to a truly impressive 3100
During your Main Phase, if this card is in your GY: You can add this card to your hand, then discard 1 "Dark World" Monster.
Here, let me give you another example of that