The symbol you should look for is a black star, as it means it's considered a rare card
Pretty much every Pokemon in these four decks are weak to Electric-type moves, so just be sure to stick with that, and clearing the challenges shouldn't be an issue
Furthermore, any card that references Black Lotus is often a hot commodity or notably powerful due the baseline power and inherent cachet that comes with the name Lotus for mages
Prime pulls included: Hops Zacian ex SIR #186 A heartfelt, story-driven masterpiece valued at $250$400 raw, PSA 10s soaring higher
However, there are some other notable options to keep our board safe: Void Grafter and Steely Resolve are nice answers to targeted removal, Etchings of the Chosen is a cool way to keep our important eldrazi alive, and Vile Redeemer can help us rebuild after a board wipe