Harvester of Souls is a staple in such lists already, so getting it with a one-mana discount and a built-in sac ability is too good a deal to pass up
Overlord of the Boilerbilges can either be a 6-mana 5/5 red creature that can remove something (or hit face) with its attack trigger, or just a burn spell for 4 mana
While there have been a handful of spells with no mana cost (most with suspenda trend that Modern Horizons 2 continues in earnest), there has never in the history of the game been a "normal" creature with no mana cost
(Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.) Number 88 Language English Legal Formats Alchemy, Brawl, Commander, Competitive Brawl, Historic, Legacy, Modern, Pauper, Pioneer, Standard, Timeless, Vintage
#1: WHEN TO MULLIGAN Veterans of lightning-fast eternal formats like to joke that the mulligan choice is their early game, but thats not really untrue for them, or for us
Delighted Halfling - The best mana dork since Birds of Paradise