The 71 new cards in the decks are set on the world of Ikoria, but the reprints can be from anywhere. There are a handful of cards from the main Ikoria set in these decks in the reprint slots, but the number is fairly small. The cards are only legal in Eternal formats like Legacy, Vintage, and Pauper.

Link to complete decklist:

https://magic.wizards.com/en/articles/archive/news/symbiotic-swarm-2020-04-06

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