The reason that matters is because Genetic Apex came with 266 cards to collect (along with secret rares on top of that) divided up over the three separate pack types (Charizard, Mewtwo, and Pikachu)
(2013-04-15) Turn overwrites all previous effects that set the targeted creature's power or toughness to specific values
It is usually very easy to cheat the Hammer onto one of your creatures with the help of Sigardas Aid or Puresteel Paladin and the payoff is always huge
The other sets also have a whole variety of other types of cards including: die-cut embossed cards, animation stick on cards, clear cards, puzzle cards, TV episode cards, sticker cards, film frame cards and first appearance hologram cards
This includes when you attack, during your upkeep before you draw for the turn, and even on your opponents turn
For the sealed-box collector, this is the ETB to keep unopened