Its not necessarily the most-played, or the most powerful, but a look at the 20 cards that on any given day of the week, float to the top of a slightly larger pool of cards that made waves this year
Japanese cards bought in Tokyo are not legal for sanctioned tournaments outside Japantheyre for collection, casual play, or play in Japan only
Even with those differences, one thing stays true in every Bracket: A strong deck is cohesive
What affects the value of The Pieces Are Coming Together
Then you can force each foe to exile-draw their first card drawn in their draw step which forces them to play catch up and really hurts control decks that flip over stuff like Counterspell
The first duel in each campaign also acts as a tutorial, as they're scripted and explain everything step-by-step