And when its night, any permanent card that any player owns that has a nightbound keyword on it, much like Tovolar above does, will come in on their night side
Itll never be as big as you want it to be, which is why its sitting here at #15 on the list
You lose out on the spell if you use these to make an early land drop, but that just puts them on par with MDFCs

Arguel's Blood Fast Bandit's Talent Black Market Connections Braids's Frightful Return Braska's Final Aeon Call of the Ring Chains of Mephistopheles Coercive Impetus Construct a Cosmic Cube Dark Prophecy Demonic Covenant Demonic Lore Discreet Retreat Dockside Chef Echo of Death's Wail Elspeth's Nightmare Erebos, Bleak-Hearted Erebos, God of the Dead Forbidden Crypt Gravestorm Greed Greed's Gambit Grisly Transformation Hateful Eidolon Infernal Scarring Infernal Tribute Krovikan Fetish Krovikan Plague Lich Lich's Mastery Lithoform Blight Lord Skitter's Blessing Midnight Oil Mindless Conscription Mornsong Aria Necrodominance Necromancer's Stockpile Necropotence Nihilistic Glee Null Profusion Oath of Lim-Dl Obsessive Pursuit One Ring to Rule Them All Origin of Black Widow Out of the Tombs Phyrexian Arena Phyrexian Etchings Raiders' Spoils Robot Domination Rune of Mortality Scavenged Weaponry Scion of Halaster Scourgemark Sicken Soulreaper of Mogis Summon: Anima Tainted Well Teval's Judgment The Cloning of Shredder The Creation of Avacyn The Cruelty of Gix The Death of Gwen Stacy The Eldest Reborn The House Grows Hungry The Long Reach of Night The Revelations of Ezio The Rise of Sozin The Toymaker's Trap Tymaret Calls the Dead Underworld Connections Vampiric Rites Vampirism

This was the motivation to create a website dedicated to collecting
In the same way that you can't cast a spell if you can't get the proper mana, mana is also a limiting factor when it comes to deck building