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.

Whenever one or more +1/+1 counters are put on a permanent you control, you may pay {1}. If you do, create a 1/1 colorless Servo artifact creature token. {3}, {T}: Choose a counter on target permanent or player. Give that permanent or player another counter of that kind.

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

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

{1}, {T}: Add {W}{U}.

Planeswalkers you control have "[0]: Proliferate" and "[−12]: Take an extra turn after this one." Whenever you cast a noncreature spell, choose a counter on target permanent. Put an additional counter of that kind on that permanent.

{T}: Add one mana of any color among legendary creatures and planeswalkers you control.

You may look at the top card of your library any time. You may cast artifact spells and colorless spells from the top of your library. {T}, Pay 1 life: Exile the top card of your library.

If one or more +1/+1 counters would be put on an artifact or creature you control, that many plus one +1/+1 counters are put on it instead. {1}{G}, {T}: Put a +1/+1 counter on target artifact or creature you control. Activate only as a sorcery. Cycling {2} ({2}, Discard this card: Draw a card.)

{1}, {T}: Add {G}{W}.

{1}: Look at the top three cards of your library, then put them back in any order. {T}: Draw a card, then put Sensei's Divining Top on top of its owner's library.

{1}, {T}: Add {G}{U}.

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

Equipped creature gets +2/+2 and has protection from white and from blue. Whenever equipped creature deals combat damage to a player, put a +1/+1 counter on a creature you control, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.) Equip {2}

{T}: Add {C}. {T}: Add {W} or {U}. Talisman of Progress deals 1 damage to you.

This spell costs {X} less to cast, where X is the greatest power among creatures you control. {T}: Add {G}{G}. You gain 2 life. Whenever a nontoken creature enters the battlefield under your control, put a +1/+1 counter on it and draw a card.

Whenever you untap one or more permanents during your untap step, put that many time counters on The Millennium Calendar. {2}, {T}: Double the number of time counters on The Millennium Calendar. When there are 1,000 or more time counters on The Millennium Calendar, sacrifice it and each opponent loses 1,000 life.

Sacrifice an artifact: Put a +1/+1 counter on Arcbound Ravager. Modular 1 (This creature enters the battlefield with a +1/+1 counter on it. When it dies, you may put its +1/+1 counters on target artifact creature.)

Converge — Crystalline Crawler enters the battlefield with a +1/+1 counter on it for each color of mana spent to cast it. Remove a +1/+1 counter from Crystalline Crawler: Add one mana of any color. {T}: Put a +1/+1 counter on Crystalline Crawler.

At the beginning of combat on your turn, choose a kind of counter at random that Crystalline Giant doesn't have on it from among flying, first strike, deathtouch, hexproof, lifelink, menace, reach, trample, vigilance, and +1/+1. Put a counter of that kind on Crystalline Giant.

This spell costs {1} less to cast for each artifact you control. When Emry, Lurker of the Loch enters the battlefield, mill four cards. {T}: Choose target artifact card in your graveyard. You may cast that card this turn. (You still pay its costs. Timing rules still apply.)

Whenever an opponent casts their first noncreature spell each turn, draw a card unless that player pays {X}, where X is Esper Sentinel's power.

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

Each player who has cast a nonartifact spell this turn can't cast additional nonartifact spells.

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

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

Hangarback Walker enters the battlefield with X +1/+1 counters on it. When Hangarback Walker dies, create a 1/1 colorless Thopter artifact creature token with flying for each +1/+1 counter on Hangarback Walker. {1}, {T}: Put a +1/+1 counter on Hangarback Walker.

Indestructible As long as your devotion to white is less than five, Heliod isn't a creature. Whenever you gain life, put a +1/+1 counter on target creature or enchantment you control. {1}{W}: Another target creature gains lifelink until end of turn.

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.) Ward {4} Whenever an artifact enters the battlefield under your control, put a +1/+1 counter on Kappa Cannoneer and it can't be blocked this turn.

{W}: Exile target card from a graveyard. If it was a permanent card, put a +1/+1 counter on Lion Sash. Equipped creature gets +1/+1 for each +1/+1 counter on Lion Sash. Reconfigure {2} ({2}: Attach to target creature you control; or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)

Prevent all combat damage that would be dealt to attacking artifact creatures you control. Whenever one or more artifact creatures enter the battlefield under your control, draw a card. This ability triggers only once each turn.

Master of Etherium's power and toughness are each equal to the number of artifacts you control. Other artifact creatures you control get +1/+1.

Mindless Automaton enters the battlefield with two +1/+1 counters on it. {1}, Discard a card: Put a +1/+1 counter on Mindless Automaton. Remove two +1/+1 counters from Mindless Automaton: Draw a card.

Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.) {T}: Add {G}, {W}, or {U}.

Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.) Whenever you cast an artifact spell, put a +1/+1 counter on Patchwork Automaton.

Whenever you cast an artifact spell, create a 1/1 colorless Thopter artifact creature token with flying. {1}{U}, Sacrifice two artifacts: Draw a card.

Modular 2 (This creature enters the battlefield with two +1/+1 counters on it. When it dies, you may put its +1/+1 counters on target artifact creature.) {T}, Sacrifice an artifact: Search your library for a Construct card, reveal it, put it into your hand, then shuffle.

Toxic 1 (Players dealt combat damage by this creature also get a poison counter.) Skrelv, Defector Mite can't block. {W/P}, {T}: Choose a color. Another target creature you control gains toxic 1 and hexproof from that color until end of turn. It can't be blocked by creatures of that color this turn. ({W/P} can be paid with either {W} or 2 life.)

{T}: Put a +1/+1 counter on each artifact creature you control.

As Stenn, Paranoid Partisan enters the battlefield, choose a card type other than creature or land. Spells you cast of the chosen type cost {1} less to cast. {1}{W}{U}: Exile Stenn. Return it to the battlefield under its owner's control at the beginning of the next end step.

Reach, trample, protection from multicolored Stonecoil Serpent enters the battlefield with X +1/+1 counters on it.

Flying Whenever you cast a historic spell, return target creature card with mana value 3 or less from your graveyard to the battlefield. (Artifacts, legendaries, and Sagas are historic.)

Affinity for artifacts Flying When Thought Monitor enters the battlefield, draw two cards.

Artifact, instant, and sorcery spells you cast cost {1} less to cast. {7}: If you both own and control Urza, Lord Protector and an artifact named The Mightstone and Weakstone, exile them, then meld them into Urza, Planeswalker. Activate only as a sorcery.

Whenever you cast an artifact spell, draw a card.

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.) When Venerated Loxodon enters the battlefield, put a +1/+1 counter on each creature that convoked it.

Trample When Verdurous Gearhulk enters the battlefield, distribute four +1/+1 counters among any number of target creatures you control.

Walking Ballista enters the battlefield with X +1/+1 counters on it. {4}: Put a +1/+1 counter on Walking Ballista. Remove a +1/+1 counter from Walking Ballista: It deals 1 damage to any target.

Whenever a creature enters the battlefield under your control, put a +1/+1 counter on each creature you control.

If one or more +1/+1 counters would be put on a creature you control, that many plus one +1/+1 counters are put on it instead.

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

Draw three cards, then put two cards from your hand on top of your library in any order.

Return target nonland permanent you don't control to its owner's hand. Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Search your library for an artifact or enchantment card, reveal it, then shuffle and put that card on top.

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

If you control a commander, you may cast this spell without paying its mana cost. Creatures you control gain indestructible until end of turn.

Search your library for an instant or sorcery card, reveal it, then shuffle and put that card on top.

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.) Destroy target artifact or enchantment.

{T}: Add {W}.

{T}: Add {G}. Channel — {1}{G}, Discard Boseiju, Who Endures: Destroy target artifact, enchantment, or nonbasic land an opponent controls. That player may search their library for a land card with a basic land type, put it onto the battlefield, then shuffle. This ability costs {1} less to activate for each legendary creature you control.

Botanical Sanctum enters the battlefield tapped unless you control two or fewer other lands. {T}: Add {G} or {U}.

Bountiful Promenade enters the battlefield tapped unless you have two or more opponents. {T}: Add {G} or {W}.

({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.

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

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

({T}: Add {G}.)

Glacial Fortress enters the battlefield tapped unless you control a Plains or an Island. {T}: Add {W} or {U}.

({T}: Add {W} or {U}.) As Hallowed Fountain enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Hinterland Harbor enters the battlefield tapped unless you control a Forest or an Island. {T}: Add {G} or {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.)

Llanowar Reborn enters the battlefield tapped. {T}: Add {G}. Graft 1 (This land enters the battlefield with a +1/+1 counter on it. Whenever a creature enters the battlefield, you may move a +1/+1 counter from this land onto it.)

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

{T}: Add {C}. {W/U}, {T}: Add {W}{W}, {W}{U}, or {U}{U}.

({T}: Add {W}.)

({T}: Add {W}.)

Razorverge Thicket enters the battlefield tapped unless you control two or fewer other lands. {T}: Add {G} or {W}.

Rejuvenating Springs enters the battlefield tapped unless you have two or more opponents. {T}: Add {G} or {U}.

Sea of Clouds enters the battlefield tapped unless you have two or more opponents. {T}: Add {W} or {U}.

Seachrome Coast enters the battlefield tapped unless you control two or fewer other lands. {T}: Add {W} or {U}.

Seaside Citadel enters the battlefield tapped. {T}: Add {G}, {W}, or {U}.

{T}: Add {U}.

({T}: Add {G}, {W}, or {U}.) Spara's Headquarters enters the battlefield tapped. Cycling {3} ({3}, Discard this card: Draw a card.)

Sunpetal Grove enters the battlefield tapped unless you control a Forest or a Plains. {T}: Add {G} or {W}.

({T}: Add {G} or {W}.) As Temple Garden enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

{T}: Add {G}.

(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.