That's the "kindness" part: no 1-shotting some random schmuck with Tainted Strike and then continuing the game for hours, we're killing everyone all at once
Legendary Creature - Spirit Advisor Color tag templates(None) Karmic Guide Flying, protection from black Echo (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.) When this creature enters, return target creature card from your graveyard to the battlefield
Its also an enchantment, and some decks will use this card with extra synergies
Intruder Alarm was reprinted in the Wilds of Eldraine: Enchanting Tales and combines with as few as one other card to provide infinite creatures
The only black bordered 13 Mana Spell - Emrakul, the Promised End This card makes me think of the Eldritch Moon Pro Tour
And, as for the best selling card of the year, that would be the card ranked fifth on this list: Lrien Revealed from Universes Beyond: The Lord of the Rings, Tales of Middle-Earth