Its a great and mana efficient removal versus Mono Red and other aggro, but unlike Epic Downfall, its never a dead card
Luckily for those willing to wield such power, Necropotence was reprinted as part of Wilds of Eldraine's Enchanting Tales bonus sheet (in several versions, including the Anime alternate style), driving its price down
It is perfect for commanding players as long as your playgroup tolerates using proxies
Players are going to crack a ton of Masters 25 packs in search of Jace, the Mind Sculptor, which is a good thing for Wizards (because they'll sell a ton of packs) and a good thing for players (since it will increase the supply of the other cards in Masters 25 , making them cheaper and more accessible)
But, the ability doesn't just limit this to creatures, so any other source of damage on your turn will be doubled