As in these are cards that have been released and then removed from the gaming scene through becoming disallowed in every format
Set symbols are an easy and quick way to figure out what set your card has come from
This means that abilities that trigger whenever a creature attacks won't trigger when these tokens enter attacking
Lets be honest while some are going to play this because they have a lot of creatures that care about counters, most are going to be equipping this to silly things like Kiora, Behemoth Beckoner (7/7 for 3 mana) or Teferi, Time Raveler, or Narset, Parter of Veils, or Jace Beleren, or Wrenn and Six
Slot #8: Foil rare or mythic Pretty standard, but again, 92% to be a rare and 8% to be a mythic
Menger sponges can be built with various materials, from LEGO bricks to index cards