Consider

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

Jwar Isle Refuge

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {U} or {B}.

Storm of Saruman

Ward {3}
Whenever you cast your second spell each turn, copy it, except the copy isn't legendary. You may choose new targets for the copy. (A copy of a permanent spell becomes a token.)

Submerged Boneyard

This land enters tapped.
{T}: Add {U} or {B}.

Kindred Discovery

As this enchantment enters, choose a creature type.
Whenever a creature you control of the chosen type enters or attacks, draw a card.

Talrand, Sky Summoner

Whenever you cast an instant or sorcery spell, create a 2/2 blue Drake creature token with flying.

Nazgûl

Deathtouch
When this creature 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.

Orcish Bowmasters

Flash
When this creature enters and whenever an opponent draws a card except the first one they draw in each of their draw steps, this creature deals 1 damage to any target. Then amass Orcs 1.

Island

Arcane Signet

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

Swamp

Minas Morgul, Dark Fortress

Minas Morgul enters tapped.
{T}: Add {B}.
{3}{B}, {T}: Put a shadow counter on target creature. For as long as that creature has a shadow counter on it, it's a Wraith in addition to its other types. (A creature with shadow can block or be blocked by only creatures with shadow.)

Raise the Palisade

Choose a creature type. Return all creatures that aren't of the chosen type to their owners' hands.

Gandalf, Friend of the Shire

Flash
You may cast sorcery spells as though they had flash.
Whenever the Ring tempts you, if you chose a creature other than Gandalf as your Ring-bearer, draw a card.

Sauron, the Necromancer

Menace
Whenever Sauron 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.

Sunken Hollow

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

Gitaxian Probe

({U/P} can be paid with either {U} or 2 life.)
Look at target player's hand.
Draw a card.

Drowned Catacomb

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

The Black Gate

As The Black Gate enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {B}.
{1}{B}, {T}: Choose a player with the most life or tied for most life. Target creature can't be blocked by creatures that player controls this turn.

Command Tower

Serum Visions

Ponder

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

Dismal Backwater

Frantic Search

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

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.

An Offer You Can't Refuse

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

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.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Sol Ring

Night's Whisper

Sam's Desperate Rescue

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

Evolving Wilds

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Canoptek Wraith

Wraith Form — This creature can't be blocked.
Transdimensional Scout — When this creature 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.

Reliquary Tower

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

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Birthday Escape

Mystic Sanctuary

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

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.)

Brainstorm

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

Claim the Precious

Destroy target creature. The Ring tempts you.

Sign in Blood

Target player draws two cards and loses 2 life.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice this artifact: Draw a card.

Gríma, Saruman's Footman

Gríma can't be blocked.
Whenever Gríma deals combat damage to a player, that player exiles cards from the top of their library until they exile an instant or sorcery card. You may cast that card without paying its mana cost. Then that player puts the exiled cards that weren't cast this way on the bottom of their library in a random order.

Dark Ritual

Pongify

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

Levitation

Rivendell

Rivendell enters tapped unless you control a legendary creature.
{T}: Add {U}.
{1}{U}, {T}: Scry 2. Activate only if you control a legendary creature.

Archmage Emeritus

Magecraft — Whenever you cast or copy an instant or sorcery spell, draw a card.

Changeling Outcast

Changeling (This card is every creature type.)
This creature can't block and can't be blocked.

Feed the Swarm

Destroy target creature or enchantment an opponent controls. You lose life equal to that permanent's mana value.

Infernal Grasp

Destroy target creature. You lose 2 life.

Dimir Signet

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.

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.

Inherited Envelope

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

Choked Estuary

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

Ringwraiths

When this creature 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 this card from your graveyard to your hand.

Barad-dûr

Barad-dûr enters tapped unless you control a legendary creature.
{T}: Add {B}.
{X}{X}{B}, {T}: Amass Orcs X. Activate only if a creature died this turn.

Glorious Gale

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

Soothing of Sméagol

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

Negate

Thought Vessel

Go for the Throat

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

Treasure Cruise

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Draw three cards.

Swan Song

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

Mirkwood Bats

Flying
Whenever you create or sacrifice a token, each opponent loses 1 life.

Counterspell

Witch-king, Bringer of Ruin

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

Underground River

{T}: Add {C}.
{T}: Add {U} or {B}. This land deals 1 damage to you.

Arcane Denial

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.
You draw a card at the beginning of the next turn's upkeep.

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.

Idol of Oblivion

{T}: Draw a card. Activate only if you created a token this turn.
{8}, {T}, Sacrifice this artifact: Create a 10/10 colorless Eldrazi creature token.