Gate Guardian is a card trader R and the materials are minibox R. Also, Paradox Brothers still have their Labyrinth Wall related cards to be used as their drop and level up reward.
Volcanics have 2 of their members being mainbox UR, and Axel has no Volcanic cards left to be used as drop or level up reward.
There's a very good reason why we will never have Scattershot, it's one of those cards that should never be considered when thinking about what cards a character will provide us with, as there's no chance we're going to get them to begin with.
Anonymous
Kaien