In the case of the decklists you find occasionally under the Decks tab of the store, the gem value is quite inflated
(2021-06-18) Choices made for permanents as they entered the battlefield are remembered when they phase in
there's the Unglued cracked-egg symbol, there is a rooster head, a straight-up chicken, there's a glasses and a mustache, a goblin head, and I'm not even sure what the lower left thing is
(2021-07-23) Due to a recent rules change to cascade, not only do you stop exiling cards if you exile a nonland card with lesser mana value than the spell with cascade, but the resulting spell you cast must also have lesser mana value
In multiplayer games, only one opponent is required to have three or more poison counters for corrupted abilities to take notice, not all of them
Amazons algorithm-driven pricing means booster boxes may drop 15-30% during low-demand periods (typically mid-set lifecycle before nostalgia kicks in)