Not physically
If they were made anywhere else, they would not be included, but since they are created by Maro himself, and they are used in an official tournament, they can truly be classified as Magic Rarities
Pokemon Error, Erratum, or Misprint Pokemon cards: Misprinted cards can sometimes confuse newer players, as small mistakes like off-centering, lines, crimping, and unusual swirls or ink splatter from occasional misprints can make real cards look fake
Its an excellent combo with cards that can take off the -1/-1 counters for profit or that can transfer counters from one creature onto another
You want lots of instant-speed ways for cards to leave your graveyard, and if a player is hating on your graveyard, at least you get treasure for it