You can buy gems in Arenas store for actual cash (or cash alternatives), earn them through Draft rewards, or occasionally through events
Then you need two copies of Myr Retriever, a rather forgettable card that lets you bring back another artifact card from your graveyard to your hand
The more destroy all creatures cards you play, the more of a liability mana dorks become
I certainly think hes on to something
Stoke provides aggressive decks with other direct damage spells like Shock and Lightning Strike just enough burn damage for it to be a much more reliable win condition
Even commodities with clear levels of use-value demand like gasoline, eggs, or palladium fluctuate in price for similar reasons, a combination of demand, investment speculation, and, if not always nostalgia, at least some form of emotional connection to a product that seems stronger than its value in use or consumption