Thinking about this even more, let's just completely disregard Greedy Dice from this picture. Jirachi Prism Star and Peonia will be a two card combo that pretty much any aggro deck could fit in to take an extra prize for a turn. They're both easily searched, since you can just Quick Ball or Ultra Ball for Jirachi and Tapu Lele-GX. Also, since Peonia goes into the discard pile instead of the prizes like Gladion, you can get it back with VS Seeker, potentially doing it again (though you'd also need Scoop Up Net and not every Expanded deck plays Scoop Up Net). But honestly though, you won't even need Scoop Up Net, as all you need is just one turn of taking an extra prize with Jirachi to swing the game in your favor. I could genuinely see this combo being a problem.
However, I definitely don't want Peonia getting banned. Being able to store cards in the prizes for later is huge, and could actually open up a brand new era of Expanded where we can use prize cards as a resource. Imagine, you use Peonia, put a Professor's Research (or any card you want for next turn) into your prizes while taking what you need out of the prizes, taking a KO and then grabbing the Professor's Research for next turn. That's so good, and opens up a bunch of new plays for the game. I will be severely disappointed if Peonia gets banned, if anything Jirachi Prism Star should be the banned card here.
