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 one mana of any color in your commander's color identity.

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

Change the text of target spell or permanent by replacing all instances of one creature type with another. The new creature type can't be Wall. (This effect lasts indefinitely.)

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

Flying

{T}: Add one mana of any color.

({T}: Add {B} or {R}.)

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

{T}, Pay 1 life, Sacrifice Bloodstained Mire: Search your library for a Swamp or Mountain card, put it onto the battlefield, then shuffle.

({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 a Sliver deals combat damage to a player, its controller may create a 1/1 colorless Sliver creature token.

All Slivers have "{1}, Sacrifice this permanent: This permanent deals 1 damage to any target."

All Slivers have "{1}, Sacrifice this permanent: Prevent the next 1 damage that would be dealt to target player, planeswalker, or Sliver creature this turn."

As Cavern of Souls enters the battlefield, choose a creature type.

{T}: Add {C}.

{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type, and that spell can't be countered.

Lands you control have "{T}: Add one mana of any color."

{T}: Add one mana of any color.

Sliver creatures you control have flying and haste.

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

All Slivers have "{T}: Regenerate target Sliver."

All Slivers have shroud. (They can't be the targets of spells or abilities.)

Destroy all creatures. They can't be regenerated.

All Slivers have "Sacrifice this permanent: You gain 3 life."

Indestructible

{T}: Add one mana of any color.

Search your library for a card, put that card into your hand, then shuffle.

Search your library for a creature card, reveal that card, put it into your hand, then shuffle.

{2}, {T}: You gain 5 life. Shuffle Elixir of Immortality and your graveyard into their owner's library.

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

{T}: Add one mana of any color that a land an opponent controls could produce.

{T}: Add one mana of any color that a land an opponent controls could produce.

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

Sliver creatures you control have flying.

All Slivers have "{T}: Add one mana of any color."

({T}: Add {W} or {B}.)

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

Search your library for a green creature card with mana value X or less, put it onto the battlefield, then shuffle. Shuffle Green Sun's Zenith into its owner's library.

({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.

All Slivers have "When this permanent enters the battlefield, destroy target artifact or enchantment."

Activated abilities of creatures cost {1} less to activate. This effect can't reduce the mana in that cost to less than one mana.

({T}: Add {W}, {B}, or {G}.)

Indatha Triome enters the battlefield tapped.

Cycling {3} ({3}, Discard this card: Draw a card.)

({T}: Add {R}, {G}, or {W}.)

Jetmir's Garden enters the battlefield tapped.

Cycling {3} ({3}, Discard this card: Draw a card.)

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

Ketria Triome enters the battlefield tapped.

Cycling {3} ({3}, Discard this card: Draw a card.)

Whenever a Sliver you control attacks, defending player loses 1 life.

Sliver creatures you control have "{T}: Add one mana of any color."

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

Sliver creatures you control get +3/+3.

All Sliver creatures get +2/+2.

At the beginning of your upkeep, you may look at the top three cards of your library, then put them back in any order.

{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 one mana of any color among legendary creatures and planeswalkers you control.

All Sliver creatures get +1/+1.

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

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

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

At the beginning of your upkeep, if you have four or more creature cards in your graveyard, you may return target creature card from your graveyard to your hand.

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

{T}, Pay 1 life, Sacrifice Polluted Delta: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.

Sliver creatures you control get +1/+1.

All Sliver creatures have flying.

All Slivers have "If this permanent would be put into a graveyard, you may put it on top of its owner's library instead."

{2}, {T}, Sacrifice a creature: Search your library for a creature card that shares a creature type with the sacrificed creature and has mana value equal to 1 plus that creature's mana value. Put that card onto the battlefield, then shuffle. Activate only as a sorcery.

({T}: Add {W}, {U}, or {B}.)

Raffine's Tower enters the battlefield tapped.

Cycling {3} ({3}, Discard this card: Draw a card.)

({T}: Add {U}, {R}, or {W}.)

Raugrin Triome enters the battlefield tapped.

Cycling {3} ({3}, Discard this card: Draw a card.)

Put target creature card from a graveyard onto the battlefield under your control. You lose life equal to its mana value.

({T}: Add {R} or {W}.)

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

({T}: Add {R}, {W}, or {B}.)

Savai Triome enters the battlefield tapped.

Cycling {3} ({3}, Discard this card: Draw a card.)

{T}, Pay 1 life, Sacrifice Scalding Tarn: Search your library for an Island or Mountain card, put it onto the battlefield, then shuffle.

All Slivers have "{T}: Target player mills a card."

As Secluded Courtyard enters the battlefield, choose a creature type.

{T}: Add {C}.

{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type or activate an ability of a creature source of the chosen type.

{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.

Sliver creatures you control have vigilance. (Attacking doesn't cause them to tap.)

Slivers can't be blocked except by Slivers.

All Sliver creatures have flanking. (Whenever a creature without flanking blocks a Sliver, the blocking creature gets -1/-1 until end of turn.)

All Sliver creatures get +1/+1.

{T}: Add {C}.

{T}: Add one mana of any color. Spend this mana only to cast a Sliver spell.

{5}, {T}: Create a 1/1 colorless Sliver creature token. Activate only if you control a Sliver.

Sliver creatures you control have indestructible. (Damage and effects that say "destroy" don't destroy them.)

All Sliver creatures get +1/+1 for each other Sliver on the battlefield.

{3}: Search your library for a Sliver card, reveal that card, put it into your hand, then shuffle.

{3}: Gain control of target Sliver. (This effect lasts indefinitely.)

{2}: Create a 1/1 colorless Sliver creature token.

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

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

Spara's Headquarters enters the battlefield tapped.

Cycling {3} ({3}, Discard this card: Draw a card.)

Whenever a Sliver becomes blocked, that Sliver gets +1/+1 until end of turn for each creature blocking it.

Sliver creatures you control have "Whenever this creature is dealt damage, it deals that much damage to target player or planeswalker."

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

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

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

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

Sliver creatures you control have first strike. (They deal combat damage before creatures without first strike.)

Exile target creature. Its controller gains life equal to its power.

Whenever a Sliver deals combat damage to a player, its controller may draw a card.

Sliver creatures you control have lifelink. (Damage dealt by a Sliver creature you control also causes you to gain that much life.)

Sliver creatures you control have "Whenever this creature deals combat damage to a player, put a +1/+1 counter on it."

({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.

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom of your library in a random order.)

Sliver spells you cast have cascade.

Activated abilities of creatures you control cost {2} less to activate. This effect can't reduce the mana in that cost to less than one mana.

(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.

Search your library for a card, then shuffle and put that card on top. You lose 2 life.

Sliver creatures you control have deathtouch. (Any amount of damage a creature with deathtouch deals to a creature is enough to destroy it.)

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

{T}: Add {C}.

{1}{B}, {T}: Put target creature card from your graveyard on top of your library.

As Ward Sliver enters the battlefield, choose a color.

All Slivers have protection from the chosen color.

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

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

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

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

Search your library for a creature card, reveal it, then shuffle and put the card on top.

Destroy all creatures. They can't be regenerated.

({T}: Add {U}, {B}, or {R}.)

Xander's Lounge enters the battlefield tapped.

Cycling {3} ({3}, Discard this card: Draw a card.)

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

Zagoth Triome enters the battlefield tapped.

Cycling {3} ({3}, Discard this card: Draw a card.)

({T}: Add {B}, {R}, or {G}.)

Ziatora's Proving Ground enters the battlefield tapped.

Cycling {3} ({3}, Discard this card: Draw a card.)