While the format did have Thoughtseize, beyond that, it lacked cards like Force of Will or Wasteland, which have historically helped keep degenerate combo decks in check without having to play very narrow answers that only hit one or two decks
When Life of the Party enters the battlefield, if it's not a token, each opponent creates a token that's a copy of it
Dusk rids of all creatures beyond 3 power and then Dawn returns all the creatures from your graveyard to hand with 2 or less power so you have access to your resources after the board wipe
A modal mechanic, Spree asks that you pay at least one additional cost to cast the spell, but you could cast all of them
Well, yes, walls sort of count as defenders but actually no
Thus far, it appears the set is going to be another success for Wizards of the Coast