>Fundamentally having more cards is bad, because it increases variance in what you can draw. StS has a number of enemies that shuffle bad cards into your deck,

>Fundamentally having more cards is bad, because it increases variance in what you can draw. StS has a number of enemies that shuffle bad cards into your deck, so this dillution works both ways. On higher difficulties more of these cards get shuffled into your deck. Trying a "thin" strategy with no countermeasures in such a fight (high damage output to end the fight fast?) can get you railroaded. You also start out with 10 starters that you want to dillute because virtually any card is better than them. Cards with "draw" and "exhaust" written on them also let you workaround the problem of drawing starter or negative effect cards. Picking up one or two versatile 2-cost cards early (attack or block card) can give you a good way to use your energy even if you draw mostly starters or negative effect cards while avoiding excessive deck dillution later on. StS does offer you worse cards at the beginning of the game, and limited ways to remove or upgrade these cards, so picking up too many cards can burden you later on. Really to be good at StS deckbuilding mostly requires you to know which enemies will come up when and building your deck sufficiently to survive them without shooting yourself in the foot long term too much. Jorbs is usually focused on building his deck to beat the hardest fight in the game while absorbing the minimum deadweight to survive until that point. Watching a stream can give you a rough idea of what a good "pace" for adding new cards into your deck is.