Those first cards are useful, but to properly challenge the islands eight elemental Club Masters, Pokmon Trading Card Game requires you to cultivate more powerful decks that play to different types of advantages and feature cards you pull from booster packs won by dueling NPCs
These are very likely to see Standard play at minimum, but may not go past that point
Popularity and Demand Cards featuring fan-favorite Pokmon like Charizard, Pikachu, or Eeveelutions often remain valuable due to constant demand, regardless of set age
The format consists of players using 100-card decks, with each card (minus basic lands) appearing only once
Though Keith has a cube of Gamma at this point, so I guess he's already a winner
It has no rules meaning by itself, and some saga creatures don't even have Summon in the name, such as Esper Terra