Decree of Pain

Destroy all creatures. They can't be regenerated. Draw a card for each creature destroyed this way.
Cycling {3}{B}{B} ({3}{B}{B}, Discard this card: Draw a card.)
When you cycle Decree of Pain, all creatures get -2/-2 until end of turn.

Preordain

Scry 2, then draw a card. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Deep Analysis

Target player draws two cards.
Flashback—{1}{U}, Pay 3 life. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Island

Fellwar Stone

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

Sauron, the Necromancer

Menace
Whenever Sauron, the Necromancer attacks, exile target creature card from your graveyard. Create a tapped and attacking token that's a copy of that card, except it's a 3/3 black Wraith with menace. At the beginning of the next end step, exile that token unless Sauron is your Ring-bearer.

Echoing Return

Return target creature card and all other cards with the same name as that card from your graveyard to your hand.

Mind Stone

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

Borne Upon a Wind

You may cast spells this turn as though they had flash.
Draw a card.

Consider

Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
Draw a card.

Sunken Hollow

({T}: Add {U} or {B}.)
Sunken Hollow enters tapped unless you control two or more basic lands.

Mystic Sanctuary

({T}: Add {U}.)
Mystic Sanctuary enters tapped unless you control three or more other Islands.
When Mystic Sanctuary enters untapped, you may put target instant or sorcery card from your graveyard on top of your library.

Dark Ritual

One Ring to Rule Them All

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — The Ring tempts you, then each player mills cards equal to your Ring-bearer's power.
II — Destroy all nonlegendary creatures.
III — Each opponent loses 1 life for each creature card in that player's graveyard.

Lash of the Balrog

As an additional cost to cast this spell, sacrifice a creature or pay {4}.
Destroy target creature.

Thought Scour

Target player mills two cards.
Draw a card.

Talisman of Dominance

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

Reanimate

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

Drowned Catacomb

Drowned Catacomb enters tapped unless you control an Island or a Swamp.
{T}: Add {U} or {B}.

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Bojuka Bog

Bojuka Bog enters tapped.
When Bojuka Bog enters, exile target player's graveyard.
{T}: Add {B}.

Tainted Isle

{T}: Add {C}.
{T}: Add {U} or {B}. Activate only if you control a Swamp.

Sam's Desperate Rescue

Return target creature card from your graveyard to your hand. The Ring tempts you.

Nasty End

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards. If the sacrificed creature was legendary, draw three cards instead.

Uruk-hai Berserker

When Uruk-hai Berserker enters, the Ring tempts you.

Canoptek Wraith

Wraith Form — Canoptek Wraith can't be blocked.
Transdimensional Scout — When Canoptek Wraith deals combat damage to a player, you may pay {3} and sacrifice it. If you do, choose a land you control. Then search your library for up to two basic land cards which have the same name as the chosen land, put them onto the battlefield tapped, then shuffle.

Village Rites

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards.

Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Draw a card.

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.

Shelob's Ambush

Target creature gets +1/+2 and gains deathtouch until end of turn. Create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")

Darkwater Catacombs

Quick Study

Nazgûl Battle-Mace

Equipped creature has menace, deathtouch, annihilator 1, and "Whenever an opponent sacrifices a nontoken permanent, put that card onto the battlefield under your control unless that player pays 3 life." (Whenever a creature with annihilator 1 attacks, defending player sacrifices a permanent of their choice.)
Equip {3}

Swamp

Nazgûl

Deathtouch
When Nazgûl enters, the Ring tempts you.
Whenever the Ring tempts you, put a +1/+1 counter on each Wraith you control.
A deck can have up to nine cards named Nazgûl.

Ringwraiths

When Ringwraiths enters, target creature an opponent controls gets -3/-3 until end of turn. If that creature is legendary, its controller loses 3 life.
When the Ring tempts you, return Ringwraiths from your graveyard to your hand.

Gollum, Patient Plotter

When Gollum, Patient Plotter leaves the battlefield, the Ring tempts you.
{B}, Sacrifice a creature: Return Gollum from your graveyard to your hand. Activate only as a sorcery.

Lord of the Nazgûl

Flying
Wraiths you control have protection from Ring-bearers.
Whenever you cast an instant or sorcery spell, create a 3/3 black Wraith creature token with menace. Then if you control nine or more Wraiths, Wraiths you control have base power and toughness 9/9 until end of turn.

Go for the Throat

Ringsight

The Ring tempts you. Search your library for a card that shares a color with a legendary creature you control, reveal it, put it into your hand, then shuffle.

Dimir Signet

Bitter Downfall

This spell costs {3} less to cast if it targets a creature that was dealt damage this turn.
Destroy target creature. Its controller loses 2 life.

Call of the Ring

At the beginning of your upkeep, the Ring tempts you.
Whenever you choose a creature as your Ring-bearer, you may pay 2 life. If you do, draw a card.

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Claim the Precious

Destroy target creature. The Ring tempts you.

Choked Estuary

As Choked Estuary enters, you may reveal an Island or Swamp card from your hand. If you don't, Choked Estuary enters tapped.
{T}: Add {U} or {B}.

Witch-king of Angmar

Flying
Whenever one or more creatures deal combat damage to you, each opponent sacrifices a creature of their choice that dealt combat damage to you this turn. The Ring tempts you.
Discard a card: Witch-king of Angmar gains indestructible until end of turn. Tap it.

Thought Vessel

Bog Tatters

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)

Serum Visions

Witch-king, Bringer of Ruin

Flying
Whenever Witch-king, Bringer of Ruin attacks, defending player sacrifices a creature with the least power among creatures they control.

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Inherited Envelope

When Inherited Envelope enters, the Ring tempts you.
{T}: Add one mana of any color.

Glorious Gale

Counter target creature spell. If it was a legendary spell, the Ring tempts you.

Rapid Hybridization

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

Sauron's Ransom

Choose an opponent. They look at the top four cards of your library and separate them into a face-down pile and a face-up pile. Put one pile into your hand and the other into your graveyard. The Ring tempts you.

Dreadful as the Storm

Target creature has base power and toughness 5/5 until end of turn. The Ring tempts you.

Command Tower

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

Crypt Incursion

Exile all creature cards from target player's graveyard. You gain 3 life for each card exiled this way.

Night's Whisper

Birthday Escape

Soothing of Sméagol

Return target nontoken creature to its owner's hand. The Ring tempts you.

Brainstorm

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

Gollum's Bite

Target creature gets -2/-2 until end of turn.
{3}{B}, Exile Gollum's Bite from your graveyard: The Ring tempts you. Activate only as a sorcery.

Sol Ring

Sign in Blood

Target player draws two cards and loses 2 life.

The Black Breath

Creatures your opponents control get -1/-1 until end of turn. The Ring tempts you.

Pongify

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