Cards with a little acorn symbol at the bottom of the card are not tournament legal and typically feature some of the strangest abilities in Magic
Holo, short for holographic, refers to an extra shiny foil on some Pokmon cards
There are also Commander applications here, as Rogues and Ninjas are becoming a fun and popular strategy to play in the singleton format, which also cares about drawing a ton of cards whenever they deal damage
Typically they do nothing at all most of the time, what you want from a card is one that has great odds of winning the game but that also does something significant when it doesn't win the game
Amazon labels it 34% off MSRP, but given how pricey these decks have been, thats underselling it
When it was released at the end of September, it was the third expansion Wizards has released this year