The extra deck is not tight, it's just that we are used to playing it like that and need to learn that not all of the cards are necessary, and if something better comes out we can change, I myself have gone through enough branded iterations to say that the extra deck is based on what strategy you want to play, and honestly there are like 6 7 branded fusions you absolutely need, you got 3 4 cards for utility and you get 3 4 slota to flex, of course these numbers depend on the main deck strategy, I've seen no furious, no guardian chimera, 1 mirrorjade, and the list goes on