Structure decks in the GX era contained necessary cards for specific strategies, an improvement from Duel Monsters
The same way that a Pidgeotto (Team Up) Control deck focuses on milling resources from your opponents deck, Chandelure VMAXs Max Poltergeist causes you to focus on increasing the amount of Trainer cards your opponent has in hand
You can even remove blockers before your opponents can even chump block your Menace creature
A pre-con Thunder Junction Commander has triggered a sudden 545% price spike for Cerulean Wisps, a blue one-drop MTG card
Its kind of worked in a lot of ways, and copies will set you back the price of a couple of booster packs, which is more than can be said for most Un-set cards
After your target has milled that many cards, they must then exile cards until they exile a nonland card with a different name from the spell you countered