An enormous pale moon quietly reminds you that this isnt our Earth
For instance, you can cast a sorcery using flashforward only when you could normally cast a sorcery
The downside of these cards though is lots of playgroups really don't like these cards so it's rude to play them at those tables, and also their win% goes down if your opponents both hate these cards and know you run them since they will gang up and kill you (ignoring everything else) so you don't get a chance to cast them
And each of those previous cards has proven powerful and seen play across formats: Thraben Inspector, Gilded Goose, Voldaren Epicure, and now Spyglass Siren
The Scorpion Dragon text is enough for me to forgive that missed opportunity, and Magda, the Hoardmasters a great treasure payoff that turns your stack of gold into bodies and damage
The runner-up is End the Festivities