Type 4 is a format with two simple rules: everyone has infinite mana of all types but can only play one spell per turn. It combines the huge spells and multiplayer element of EDH with the interaction of eternal formats. Pushing MTG to the extreme, Type 4 offers absurd boardstates, insane blowouts, and unforeseen interactions.
Players have infinite mana of every type at all times.
Players can only cast one spell per turn.
Communal library/stack for players. Players have their own graveyard.
Starting hand size of 5.
Max hand size of 5.
Starting life is 20.
Alternate Casting Rule or ACR: Once per turn, you may cast an additional spell if it has an alternate cast that you pay and is played only from your hand.
Misc. Spells that allow you to cast spells without paying their mana cost (Spelljack, Kheru Spellsnatcher, etc.)
Defensive Ability Wins or DAW: If two infinite activated abilities are on the stack, the last one to be placed on the initial stack will always resolve first. In other words, he who instigates, loses. Here's a couple examples:
Player 1 "instigates" by activating Kazarov, Sengir Pureblood targeting a creature. Player 2 "defends" by activating Azorius Guildmage to counter the ability. Applying DAW, Player 2 will always counter Player 1's ability.
Player 1 "instigates" by activating Vampiric Dragon targeting Player 2's Combat Medic. Player 2 "defends" by activating Combat Medic to prevent the damage. Applying DAW, Player 2 will always prevent Player 1's ability.
Type 4 stack/cube with all the bells and whistles.
List is maintained here: http://cubecobra.com/cube/overview/thetype4stack
What is Type 4?
Type 4 is a format with two simple rules: everyone has infinite mana of all types but can only play one spell per turn. It combines the huge spells and multiplayer element of EDH with the interaction of eternal formats. Pushing MTG to the extreme, Type 4 offers absurd boardstates, insane blowouts, and unforeseen interactions.
Cards & Keywords that work under ACR:
Cards & Keywords that do not work under ACR:
Visual spoiler here: https://cubecobra.com/cube/list/thetype4stack?view=spoiler
1 Deathless Angel
1 Realm-Cloaked Giant
1 Serra's Emissary
1 Akroma, Angel of Wrath
1 Avacyn, Angel of Hope
1 Divine Deflection
1 March of Otherworldly Light
1 Shining Shoal
1 Unexpectedly Absent
1 Boros Fury-Shield
1 Generous Gift
1 Teferi's Protection
1 Comeuppance
1 Resounding Silence
1 Winds of Abandon
1 Farewell
Blue
1 Stratus Dancer
1 Voidmage Apprentice
1 Voidmage Prodigy
1 Brazen Borrower
1 Innocuous Insect
1 Nimble Obstructionist
1 Glen Elendra Archmage
1 Kheru Spellsnatcher
1 Metathran Aerostat
1 Mocking Doppelganger
1 Monastery Loremaster
1 Overcharged Amalgam
1 Stunt Double
1 Venser, Shaper Savant
1 Vizier of Many Faces
1 Chromeshell Crab
1 Mulldrifter
1 Sister of Silence
1 Teferi, Mage of Zhalfir
1 Vesuvan Shapeshifter
1 Draining Whelk
1 Hullbreaker Horror
1 Jin-Gitaxias, Progress Tyrant
1 Lord of Change
1 Nezahal, Primal Tide
1 Sphinx of the Final Word
1 Sphinx of Uthuun
1 Kederekt Leviathan
1 Teferi, Master of Time
1 Ertai's Meddling
1 Wash Away
1 Whispers of the Muse
1 Cyclonic Rift
1 Everdream
1 Narset's Reversal
1 Archmage's Charm
1 Disallow
1 Dominate
1 Force of Negation
1 Resounding Wave
1 Wipe Away
1 Cryptic Command
1 Dismiss
1 Fact or Fiction
1 Insidious Will
1 Last Word
1 Memory Deluge
1 Mindbreak Trap
1 Overwhelming Denial
1 Run Out of Town
1 Spell Counter
1 Summary Dismissal
1 Very Cryptic Command
1 Very Cryptic Command
1 Very Cryptic Command
1 Contradict
1 Desertion
1 Fervent Denial
1 Force of Will
1 Gale's Redirection
1 Graven Lore
1 Misdirection
1 Mystic Confluence
1 Precognitive Perception
1 Aethersnatch
1 Discontinuity
1 Draconic Lore
1 Elminster's Simulacrum
1 Spelljack
1 Sublime Epiphany
1 Supplant Form
1 Time Stop
1 Commandeer
1 Hurkyl's Final Meditation
1 Dig Through Time
1 Inspired Idea
1 Rite of Replication
1 Crush of Tentacles
1 Expropriate
1 Moonsnare Prototype
1 Leyline of Anticipation
1 Form of the Mulldrifter
1 Take Possession
1 Decree of Silence
1 Ghost-Lit Stalker
1 Consumptive Goo
1 Dark Impostor
1 Smokespew Invoker
1 Bane of the Living
1 Author of Shadows
1 Chainer, Dementia Master
1 Gravewaker
1 Kazarov, Sengir Pureblood
1 Sepulchral Primordial
1 Archfiend of Despair
1 Archon of Cruelty
1 Baleful Force
1 Infernius Spawnington III, Esq.
1 Shard of the Nightbringer
1 Spirit of the Night
1 Sorin Markov
1 Suffer the Past
1 Corpse Dance
1 Mythos of Nethroi
1 Sudden Death
1 Sudden Spoiling
1 Agonizing Demise
1 Hostile Negotiations
1 Silence the Believers
1 Wretched Confluence
1 Fated Return
1 Grave Endeavor
1 Damn
1 Path of Peril
1 Resounding Scream
1 Monomania
1 Bad Deal
1 Thought Distortion
1 Sorin's Vengeance
1 Decree of Pain
1 Rise of the Dark Realms
1 Worst Fears
1 Fevered Convulsions
1 Wound Reflection
1 Hedonist's Trove
Red
1 Jeering Instigator
1 Flowstone Overseer
1 Siege-Gang Commander
1 Stormbreath Dragon
1 Amethyst Dragon
1 Combustible Gearhulk
1 Death Kiss
1 Emissary of Grudges
1 Red Dragon
1 Molten Primordial
1 Akroma, Angel of Fury
1 Bogardan Hellkite
1 Dragon Tyrant
1 Magmatic Force
1 Myojin of Roaring Blades
1 Chandra, Awakened Inferno
1 Blast from the Past
1 Delayed Blast Fireball
1 Resounding Thunder
1 Urza's Rage
1 Grab the Reins
1 Ricochet Trap
1 Wild Ricochet
1 Riddle of Lightning
1 Word of Seizing
1 Inescapable Blaze
1 Thunderous Wrath
1 Inferno
1 Searing Wind
1 Alchemist's Gambit
1 Fight with Fire
1 Sundering Stroke
1 Explosive Singularity
1 Insurrection
1 Knollspine Invocation
1 Dictate of the Twin Gods
Green
1 Den Protector
1 Ana Battlemage
1 Timmy, Power Gamer
1 Ulvenwald Behemoth
1 Thornling
1 Vorinclex, Monstrous Raider
1 Cragplate Baloth
1 Dawnglade Regent
1 Gaea's Revenge
1 End-Raze Forerunners
1 The Tarrasque
1 Tear Asunder
1 Beast Within
1 Once and Future
1 Tornado
1 Lurking Predators
Azorius
1 Azorius Guildmage
1 New Prahv Guildmage
1 Shorikai, Genesis Engine
1 Armored Guardian
1 Swift Silence
1 Urza, Planeswalker
Dimir
1 Dimir Doppelganger
1 Ertai Resurrected
1 Silumgar's Command
1 The Scarab God
1 Callidus Assassin
1 Gyruda, Doom of Depths
1 Backlash
1 Delirium
1 Kolaghan, the Storm's Fury
1 Skull Rend
1 The Scorpion God
1 Deepfire Elemental
1 Dragonlord Kolaghan
1 Bladewing, Deathless Tyrant
1 Kaervek the Merciless
1 Tibalt, Cosmic Impostor
1 Mishra, Lost to Phyrexia
1 Vampiric Dragon
Gruul
1 Vexing Shusher
Orzhov
1 General's Enforcer
1 Anguished Unmaking
1 Profane Procession
1 Utter End
1 Inkshield
1 Ethereal Absolution
1 Merciless Eviction
1 Ashen Rider
Izzet
1 Counterflux
1 Steam Augury
1 Prophetic Bolt
1 Blast of Genius
1 Niv-Mizzet, Parun
1 Creative Outburst
1 Refuse // Cooperate
1 Magma Opus
Golgari
1 Assassin's Trophy
1 Mortality Spear
1 Back for More
1 Casualties of War
Boros
1 Captain's Maneuver
1 Deflecting Palm
1 Reflect Damage
1 Aurelia, the Warleader
1 Gisela, Blade of Goldnight
Simic
1 Voidslime
1 Frilled Mystic
1 Mystic Snake
1 Wavesifter
1 Colossal Skyturtle
3+ Color
1 Endless Detour
1 Void Rend
1 Deny the Witch
1 Magister Sphinx
1 Nicol Bolas, the Ravager
1 Cruel Ultimatum
1 Garza Zol, Plague Queen
1 Nicol Bolas, God-Pharaoh
1 Thraximundar
1 Nicol Bolas, Planeswalker
1 Darigaaz Reincarnated
1 Karrthus, Tyrant of Jund
1 Hit // Run
1 Riku of Two Reflections
1 Jodah, Archmage Eternal
1 Nira, Hellkite Duelist
1 Two-Headed Hellkite
Colorless
1 Surge Engine
1 Hanweir, the Writhing Township
1 Etched Monstrosity
1 Rootwire Amalgam
1 Soul of New Phyrexia
1 Ancient Stone Idol
1 Bosh, Iron Golem
1 Cityscape Leveler
1 Decimator of the Provinces
1 Ulamog, the Ceaseless Hunger
1 Ulamog, the Infinite Gyre
1 Void Winnower
1 Ugin, the Spirit Dragon
1 Scour from Existence
1 Goblin Firebomb
1 Fist of Suns
1 Emmessi Tome
1 Lithoform Engine
1 Thran Tome
1 Vedalken Orrery
1 Mindslaver
1 Kaldra Compleat
1 Aladdin's Ring
Land
1 Alchemist's Refuge
1 Blighted Cataract
1 Dark Depths
1 Gates of Istfell
1 Gold-Forge Garrison
1 Memorial to Genius
1 Mirrorpool
1 Otawara, Soaring City
1 Spitfire Bastion
1 Takenuma, Abandoned Mire
1 Throne of the High City
1 Winding Canyons
General Rules for Type 4 / Limited Infinity: https://mtg.gamepedia.com/Type_4
Type 4: A Way To Enjoy Magic Again Part I: https://articles.starcitygames.com/articles/type-4-a-way-to-enjoy-magic-again-part-i/
Type 4: A Way To Enjoy Magic Again Part II: https://articles.starcitygames.com/articles/type-4-a-way-to-enjoy-magic-again-part-ii/
Type 4: A Way To Enjoy Magic Again Part III: https://articles.starcitygames.com/articles/type-4-a-way-to-enjoy-magic-again-part-iii/
Infinite Possibilities – Playing with House Rules in Type 4, Part I: https://www.coolstuffinc.com/a/infinite-possibilities-–-playing-with-house-rules-in-type-4-part-i
Infinite Possibilities – Playing with House Rules in Type 4, Part II: https://www.coolstuffinc.com/a/infinite-possibilities-–-playing-with-house-rules-in-type-4-part-ii