Another option is to go to a specialized collectible card store, where they can verify the cards authenticity
For example, if a permanent with a finality counter on it would be put into its owner's hand from the battlefield, it does so normally
One of the interesting aspects of Modern as a format is just how important sideboard cards actually areif you look over the lists of the most played cards in the format, you'll see that it's littered with cards that show up exclusively or primarily in sideboards
8 Dragonite EX: Dragon (Ultra Rare) $188.69 Looking To The Skies EX Dragon is one of the most notable EX-era sets, featuring a collection of top-tier Dragon-type Pokemon like Dragonite among its most expensive cards
Fortunately, cards that give all your spells Flash are also ideally suited to this task
Sure, you can use Tiamat for five colors, toss in all these cards and some sort of spells and mana rocks, and see what happens