Both Alliance and Disappear are returning mechanics, originally appearing in Streets of New Capenna and Aether Revolt respectively, though you may recognize Disappear under its other name of Revolt. Alliance triggers via an ETB effect whenever a creature enters the battlefield under your control, and Disappear on the flip side triggers when a permanent you control leaves the battlefield (making it great for blink decks)
Stock tends to skew modern, making it a good place to pick up Scarlet & Violet singles , playable cards, and official sleeves or deck boxes
How can location cards combo with characters
An interesting segueing from this is how TPC will deal with the class thing going forward, with second hand Pokemon (and thus Pokemon itself) becoming ever more increasingly associated with a higher bourgeoisie and even the overclass
The sequel featured the same set of cards as the first game, plus the Team Rocket set of cards from the TCG and a few more, which increased the overall available number of cards to 445