Last Marnie card?
You can obtain this Marnie (340/S-P) promo as a participation award at the Japanese Extra Battle Day tournaments that will be held starting from December 16, 2022 at Pokémon Card Gym stores in Japan.
This Marnie promo is a Sword & Shield (alternate artwork) card reprint originally released during various Sword & Shield sets.
You can also get expanded cards in a special Extra Battle Day Promo Card Pack featuring Dedenne GX, VS Seeker and Computer Search Ace Spec. These will be distributed as prizes. There are also more promo cards coming making with a total of 10 promos to be found in these packs.
Only Expanded decks are allowed.
More details later as the website will update in the future.
The previous Extra Battle Day promo's were:
Mallow & Lana 256/S-P released in 2022, Cynthia 155/S-P released in 2021, Hau 394/SM-P, Acerola 395/SM-P, Guzma 396/SM-P and Lillie 397/SM-P released in 2019.
Update 12-12-2022: All 10 promos have been revealed from the Extra Battle Day Promo Card Pack.