Tournaments
City's: I have gone to 3 citys tornaments The most commen deck I see is a blastoise keldeo. Its also one of the best decks. I also saw a desent amount of Darkri decks.
Regionals: I have been to one regionals. I saw riqueals,fluffdragon and darkri decks. The most powerful is the darkri deck.
battle road: I have been to over 8 battle roads and they are the one of the most casual.I see a lot of different decks.
Pre releases: Are the most casual and you get 6 pack of cards and 2 at the end the 6 packs you make a deck with and then they previde energy. These packs are the next series before they come out for sale. This tournament costs $25-$30 depending on witch place you go to attend.