Return from your graveyard to the battlefield any number of target creature cards that each have a different mana value X or less.

As Agadeem, the Undercrypt enters the battlefield, you may pay 3 life. If you don't, it enters the battlefield tapped.

{T}: Add {B}.

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

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

Creatures you control have hexproof. (They can't be the targets of spells or abilities your opponents control.)

{1}{G}: Regenerate target creature.

{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.

Castle Garenbrig enters the battlefield tapped unless you control a Forest.

{T}: Add {G}.

{2}{G}{G}, {T}: Add six {G}. Spend this mana only to cast creature spells or activate abilities of creatures.

Castle Locthwain enters the battlefield tapped unless you control a Swamp.

{T}: Add {B}.

{1}{B}{B}, {T}: Draw a card, then you lose life equal to the number of cards in your hand.

Castle Vantress enters the battlefield tapped unless you control an Island.

{T}: Add {U}.

{2}{U}{U}, {T}: Scry 2.

{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.

{3}, {T} or {U}, {T}: Return target creature to its owner's hand unless its controller pays {1}.

Indestructible

Equipped creature has indestructible.

Equip {2}

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

{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 {C}.

{T}, Sacrifice a creature: You gain 1 life.

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

Ice Tunnel enters the battlefield tapped.

{T}, Sacrifice Jeweled Lotus: Add three mana of any one color. Spend this mana only to cast your commander.

{T}, Pay 1 life: Add one mana of any color.

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}.

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

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

{T}, Pay 1 life: Add {B} or {G}.

{1}, {T}, Sacrifice Nurturing Peatland: Draw a card.

Mutate {1}{B}{G}{U} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)

Trample

Whenever this creature deals combat damage to a player, return target creature card with mutate from your graveyard to your hand.

({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.

{1}{B}, Pay 2 life: Return target creature card from your graveyard to your hand.

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

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

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

Rimewood Falls enters the battlefield tapped.

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

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {B}.)

({T}: Add {B}.)

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

(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.

{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.

{T}, Pay 1 life: Add {G} or {U}.

{1}, {T}, Sacrifice Waterlogged Grove: Draw a card.

({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.

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

Woodland Chasm enters the battlefield tapped.

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

Zagoth Triome enters the battlefield tapped.

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