These will see play, but in an almost predetermined way
The three main errors I see described as 'double prints' are
According to CGC, the last one, which is printed on a plain backing and not the usual MTG or Pokmon designs, was actually a press asset used to show off the card game for a now-lost interview
Card Name Mana Cost Type Enchantment Class Rarity Uncommon rules Text (Gain the next level as a sorcery to add its ability.) When this Class enters, create a 0/4 white Wall creature token with defender.: Level 2 one or more noncreature, nonland permanents you control enter, put a +1/+1 counter on target creature you control.: Level 3 this Class becomes level 3, return target noncreature, nonland permanent card from your graveyard to the battlefield
(Yes, I would have made the Looter above targeted too if I had my way.) I'm a big believer in the idea that allowing people to figure out how to use cards in ways they wouldn't normally is a big part of what makes Magic such a compelling game
Magic: The Gathering enthusiasts have a unique opportunity to obtain a highly coveted card called The One Ring in the upcoming Lord of the Rings expansion set