Another star performer of the world of the Infinite Mono Black Combo is Magus of the Coffers
My guess is that both the cards from the main set and non-foil old-border cards need to drop a lot in price, perhaps close to 50% on average, just to get the expected value of a box down into the high-normal range
"Before you know it, I'm like Smaug the dragon hoarding the hourglasses." To be clear, Vincent does open packs - he's sitting on a respectable card collection including some sought after crown rarity gold rares, and needs to keep his decks up to date to keep winning challenges - but he never uses hourglasses
Great early computer-generated artwork (one of the first for an actual Pokemon in the TCG) means this card retains impressive value
And yes, that means the 10 SIR cards have stepped up too, all of them (but for the Mega Absol ex, I would argue) looking like they could have been the ultimate chase card in any set on their own
This variant of Hydreigon ex is number 240 in Surging Sparks