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It's closely tied to Core Set 2021 they share a lot of content and release near one anotherbut Jumpstart is a stand-alone product
You do get it for another turn, though, so your opponents can't just tap their [[Sol Ring]] and fully deny the effect
In a slow deck, your opponent might gladly choose to pay 3 life in order for your creature to be dead forever
For most decks, being restricted to only cards that cost three or more means that Keruga, the Macrosage has the same exact issue as Gyruda, Doom of Depths: you only get to play a single card over the first three turns of the game, leaving you in a position where you're often dead to aggressive decks (this gets even worse in older formats, which are faster and place a higher value on efficiency)