Some sets muddy the waters between what does and doesnt count as a showcase frame, so Ill make things simple and include any treatments that significantly alter the usual card frame
Of the new Water-type decks, Palkia ex is the strongest, and here is the best deck to use with it
I prefer Protection Racket in my drain focused decks, but you may decide to find room for Black Market Connections as an alternative
Although the deck has continued to receive meaningful support, including OP15-101-kalgara as a dedicated searcher, OP15-119-monkeydluffy and OP15-114-wyper as powerful threats from OP15, and most recently OP16-119-marshalldteach from OP16, these additions have significantly improved the deck's consistency and offensive potential
Critically, this includes Spawn and Scions