eternatus pokemon card V 116/189 - Ultra Rare - Darkness Ablaze cementing its place as a must Eternatus V - Pokemon TCG

The main reason for this is the differences in the characteristics of the cards from the English version

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Given that Duskmourn introduced a bunch of enchantment nightmares, including a couple that didnt quite make the list, you could look to enchantress synergies like Sythis, Harvest's Hand and Inquisitive Glimmer for a more concentrated way to use your nightmares

If you're building or maintaining a couple decks each season, each new release should provide a handful of upgrades for decks you already have or inspire you with an all-new deck to work toward, but the number of viable decks you have shouldn't change significantly