At the beginning of your upkeep, you may put a charge counter on Aether Vial.

{T}: You may put a creature card with mana value equal to the number of charge counters on Aether Vial from your hand onto the battlefield.

{T}: Add {C}{C}. Ancient Tomb deals 2 damage to you.

Counter target artifact or enchantment spell.

{T}: Add one mana of any color in your commander's color identity.

Sacrifice a creature: Add {C}{C}.

Astral Cornucopia enters the battlefield with X charge counters on it.

{T}: Choose a color. Add one mana of that color for each charge counter on Astral Cornucopia.

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

{1}, {T}: Put a charge counter on Brain in a Jar, then you may cast an instant or sorcery spell with mana value equal to the number of charge counters on Brain in a Jar from your hand without paying its mana cost.

{3}, {T}, Remove X charge counters from Brain in a Jar: Scry X.

({T}: Add {G} or {U}.)

As Breeding Pool enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Whenever City of Brass becomes tapped, it deals 1 damage to you.

{T}: Add one mana of any color.

Buyback {3} (You may pay an additional {3} as you cast this spell. If you do, put this card into your hand as it resolves.)

Choose a counter on target permanent or suspended card. Remove that counter from that permanent or card or put another of those counters on it.

{T}: Add {C}.

{T}, Sacrifice Command Beacon: Put your commander into your hand from the command zone.

{T}: Add one mana of any color in your commander's color identity.

When Contagion Clasp enters the battlefield, put a -1/-1 counter on target creature.

{4}, {T}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

When Contagion Engine enters the battlefield, put a -1/-1 counter on each creature target player controls.

{4}, {T}: Proliferate, then proliferate again. (Choose any number of permanents and/or players, then give each another counter of each kind already there. Then do it again.)

{T}: Put a charge counter on target artifact.

Sacrifice Coretapper: Put two charge counters on target artifact.

Counter target spell.

{T}, Sacrifice a creature: Put a charge counter on Culling Dais.

{1}, Sacrifice Culling Dais: Draw a card for each charge counter on Culling Dais.

Artifacts you control have indestructible. (Effects that say "destroy" don't destroy them. Artifact creatures with indestructible can't be destroyed by damage.)

Indestructible

Equipped creature has indestructible.

Equip {2}

Indestructible (Effects that say "destroy" don't destroy this artifact.)

At the beginning of your upkeep, you may put a charge counter on Darksteel Reactor.

When Darksteel Reactor has twenty or more charge counters on it, you win the game.

When Deepglow Skate enters the battlefield, double the number of each kind of counter on any number of target permanents.

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.

If an effect would put one or more counters on a permanent you control, it puts twice that many of those counters on that permanent instead.

At the beginning of your upkeep, choose one --

• Put a +1/+1 counter on target artifact creature.

• Put a charge counter on target noncreature artifact.

Eternity Vessel enters the battlefield with X charge counters on it, where X is your life total.

Landfall -- Whenever a land enters the battlefield under your control, you may have your life total become the number of charge counters on Eternity Vessel.

Artifact spells you cast cost {1} less to cast.

Multikicker {2} (You may pay an additional {2} any number of times as you cast this spell.)

Everflowing Chalice enters the battlefield with a charge counter on it for each time it was kicked.

{T}: Add {C} for each charge counter on Everflowing Chalice.

Landfall -- Whenever a land enters the battlefield under your control, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

If you control a commander, you may cast this spell without paying its mana cost.

Counter target noncreature spell.

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

Artifact spells you cast cost {1} less to cast.

At the beginning of combat on your turn, put a charge counter on Gavel of the Righteous.

Equipped creature gets +1/+1 for each counter on Gavel of the Righteous.

As long as Gavel of the Righteous has four or more counters on it, equipped creature has double strike.

Equip--Pay {3} or remove a counter from Gavel of the Righteous.

{2}: Put a charge counter on Gemstone Array.

Remove a charge counter from Gemstone Array: Add one mana of any color.

Whenever a player casts an instant or sorcery spell, put a number of charge counters on Geometric Nexus equal to that spell's mana value.

{6}, {T}, Remove all charge counters from Geometric Nexus: Create a 0/0 green and blue Fractal creature token. Put X +1/+1 counters on it, where X is the number of charge counters removed this way.

{T}: Add {C}.

{T}, Sacrifice Ghost Quarter: Destroy target land. Its controller may search their library for a basic land card, put it onto the battlefield, then shuffle.

({U/P} can be paid with either {U} or 2 life.)

Look at target player's hand.

Draw a card.

Whenever you cast an artifact spell, you may put a charge counter on Golem Foundry.

Remove three charge counters from Golem Foundry: Create a 3/3 colorless Golem artifact creature token.

{T}: Put a charge counter on Grindclock.

{T}: Target player mills X cards, where X is the number of charge counters on Grindclock.

Hinterland Harbor enters the battlefield tapped unless you control a Forest or an Island.

{T}: Add {G} or {U}.

Whenever you cast a spell, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

{T}: Add {C}.

{4}, {T}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)

Equip {0}

{T}: Put a charge counter on Lux Cannon.

{T}, Remove three charge counters from Lux Cannon: Destroy target permanent.

{4}, {T}: Put a charge counter on Magistrate's Scepter.

{T}, Remove three charge counters from Magistrate's Scepter: Take an extra turn after this one.

Mana Bloom enters the battlefield with X charge counters on it.

Remove a charge counter from Mana Bloom: Add one mana of any color. Activate only once each turn.

At the beginning of your upkeep, if Mana Bloom has no charge counters on it, return it to its owner's hand.

At the beginning of your upkeep, flip a coin. If you lose the flip, Mana Crypt deals 3 damage to you.

{T}: Add {C}{C}.

Counter target spell. At the beginning of your next main phase, add an amount of {C} equal to that spell's mana value.

{T}: Untap target attacking creature. Prevent all combat damage that would be dealt to and dealt by that creature this turn.

{T}: Add {U}.

{2}{U}: Put an hour counter on Midnight Clock.

At the beginning of each upkeep, put an hour counter on Midnight Clock.

When the twelfth hour counter is put on Midnight Clock, shuffle your hand and graveyard into your library, then draw seven cards. Exile Midnight Clock.

{T}: Add {U}.

{U}, {T}: Untap target legendary permanent.

{T}: Add {C}.

{1}, {T}, Sacrifice Mind Stone: Draw a card.

{T}: Add {C}{C}{C}. Spend this mana only to cast artifact spells.

{T}, Pay 1 life, Sacrifice Misty Rainforest: Search your library for a Forest or Island card, put it onto the battlefield, then shuffle.

Destroy target artifact or enchantment. Its controller gains 4 life.

If you control a commander, you may cast this spell without paying its mana cost.

Prevent all damage that would be dealt this turn by creatures your opponents control.

Orochi Hatchery enters the battlefield with X charge counters on it.

{5}, {T}: Create a 1/1 green Snake creature token for each charge counter on Orochi Hatchery.

Counter target spell.

At the beginning of your next upkeep, pay {3}{U}{U}. If you don't, you lose the game.

Sunburst (This enters the battlefield with a charge counter on it for each color of mana spent to cast it.)

Remove a charge counter from Pentad Prism: Add one mana of any color.

As Pithing Needle enters the battlefield, choose a card name.

Activated abilities of sources with the chosen name can't be activated unless they're mana abilities.

Destroy target creature. It can't be regenerated. Its controller creates a 3/3 green Ape creature token.

Whenever a creature you control becomes tapped, you may put a quest counter on Quest for Renewal.

As long as there are four or more quest counters on Quest for Renewal, untap all creatures you control during each other player's untap step.

Destroy target creature. It can't be regenerated. That creature's controller creates a 3/3 green Frog Lizard creature token.

Exile target creature. Its controller manifests the top card of their library. (That player puts the top card of their library onto the battlefield face down as a 2/2 creature. If it's a creature card, it can be turned face up any time for its mana cost.)

Rejuvenating Springs enters the battlefield tapped unless you have two or more opponents.

{T}: Add {G} or {U}.

Exile target artifact or creature. Its controller creates a 4/4 blue and red Elemental creature token.

Equipped creature gets +1/+1 and has trample and lifelink.

{1}: Permanents your opponents control lose hexproof and indestructible until end of turn.

Equip {2}

At the beginning of your upkeep or whenever you cast a green spell, put a charge counter on Shrine of Boundless Growth.

{T}, Sacrifice Shrine of Boundless Growth: Add {C} for each charge counter on Shrine of Boundless Growth.

At the beginning of your upkeep or whenever you cast a blue spell, put a charge counter on Shrine of Piercing Vision.

{T}, Sacrifice Shrine of Piercing Vision: Look at the top X cards of your library, where X is the number of charge counters on Shrine of Piercing Vision. Put one of those cards into your hand and the rest on the bottom of your library in any order.

{T}: Add {C}{C}.

When Soul-Guide Lantern enters the battlefield, exile target card from a graveyard.

{T}, Sacrifice Soul-Guide Lantern: Exile each opponent's graveyard.

{1}, {T}, Sacrifice Soul-Guide Lantern: Draw a card.

{T}: Add {C}.

{T}, Sacrifice Strip Mine: Destroy target land.

Whenever you're dealt damage, put that many charge counters on Sun Droplet.

At the beginning of each upkeep, you may remove a charge counter from Sun Droplet. If you do, you gain 1 life.

Counter target enchantment, instant, or sorcery spell. Its controller creates a 2/2 blue Bird creature token with flying.

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)

Equip {1}

You may activate abilities of creatures you control as though those creatures had haste.

{1}, {T}: Untap target creature.

{T}, Sacrifice an artifact: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Transmogrifying Wand enters the battlefield with three charge counters on it.

{1}, {T}, Remove a charge counter from Transmogrifying Wand: Destroy target creature. Its controller creates a 2/4 white Ox creature token. Activate only as a sorcery.

({T}: Add {G} or {U}.)

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)

I -- Urza's Saga gains "{T}: Add {C}."

II -- Urza's Saga gains "{2}, {T}: Create a 0/0 colorless Construct artifact creature token with 'This creature gets +1/+1 for each artifact you control.'"

III -- Search your library for an artifact card with mana cost {0} or {1}, put it onto the battlefield, then shuffle.

Whenever you roll one or more dice, put a number of charge counters on Vexing Puzzlebox equal to the result.

{T}: Add one mana of any color. Roll a d20.

{T}, Remove 100 charge counters from Vexing Puzzlebox: Search your library for an artifact card, put that card onto the battlefield, then shuffle.

Flying

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

{3}{U}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

{G}{U}, {T}: Double the number of each kind of counter on target artifact, creature, or land.

Trample, haste

If you would put one or more counters on a permanent or player, put twice that many of each of those kinds of counters on that permanent or player instead.

If an opponent would put one or more counters on a permanent or player, they put half that many of each of those kinds of counters on that permanent or player instead, rounded down.

{T}: Add {C}.

{3}, {T}, Pay life equal to the number of colors in your commanders' color identity: Draw a card.

Each land is a Forest in addition to its other land types.