pokemon trading card game darkness ablaze Sword & Shield: Butterfree VMAX Sword & Shield: Darkness Ablaze

Thats serious value, letting you bounce back from removal or set up plays with Mask of Memory

Yawgmoth's Bargain (T1, S, Block) You'll notice that the Bargain doesn't show up in Extended

The cards you can turn into creatures have to cost more than four mana, and Bello costs three, so you need Bello to stick around for a bit and you have to have several enchantments in play to really keep the pressure up

On the other hand, for products like Secret Lair drops, Commander decks, or other preconstructed / box-set supplemental products, we used the cost of buying the sealed product (which is generally lower than the cost of buying all of the cards in the product individually) from around the time the set was released (for sealed product, you'll often pay much more if you wait until the set goes out of print to try to buy it)