It lets you create a non-legendary copy of a creature that attacked
Examples of these cards include the Bobblehead series from Magics Starting with the Bobbleheads, these Commander favorites may not be the most powerful of cards or the rarest they were printed out of 500, after all but they do highlight the power of cutting down on the absolute number of serialized cards per set
A Curiously Complete Combo While the cards in Astarions Thirst might not all be winners, they do all fit in the same deck
Enter the Infinite, unlike it's affinity-based cousin is a very good card and often does read You win the game. That is what you want if you are waiting till turn 12 to do something big (although you should always protect Enter the Infinite with at least one counterspell)
So, you're either saving mana for EOT on your opponent's turn, or just
[JP] One Piece OP-12 Legacy of the Master Booster Box - Japanese - Trading Card Game OP12