Eusocial Engineering

Landfall — Whenever a land you control enters, create a 2/2 colorless Robot artifact creature token.
Warp {1}{G} (You may cast this card from your hand for its warp cost. Exile this enchantment at the beginning of the next end step, then you may cast it from exile on a later turn.)

Thought Vessel

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

Chancellor of the Tangle

You may reveal this card from your opening hand. If you do, at the beginning of your first main phase of the game, add {G}.
Vigilance, reach

Shortcut to Mushrooms

When this enchantment enters, the Ring tempts you.
At the beginning of your end step, if a permanent you controlled left the battlefield this turn, put a +1/+1 counter on target creature you control.

Gollum, Patient Plotter

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

Rampaging Baloths

Trample
Landfall — Whenever a land you control enters, create a 4/4 green Beast creature token.

The Soul Stone

Indestructible
{T}: Add {B}.
{6}{B}, {T}, Exile a creature you control: Harness The Soul Stone. (Once harnessed, its ∞ ability is active.)
∞ — At the beginning of your upkeep, return target creature card from your graveyard to the battlefield.

Gollum's Bite

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

Mana Vault

This artifact doesn't untap during your untap step.
At the beginning of your upkeep, you may pay {4}. If you do, untap this artifact.
At the beginning of your draw step, if this artifact is tapped, it deals 1 damage to you.
{T}: Add {C}{C}{C}.

Sol Ring

Mox Tantalite

Suspend 3—{0} (Rather than cast this card from your hand, pay {0} and exile it with three time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)
{T}: Add one mana of any color.

Inherited Envelope

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

Chocobo Racetrack

Landfall — Whenever a land you control enters, create a 2/2 green Bird creature token with "Whenever a land you control enters, this token gets +1/+0 until end of turn."

Bloodghast

This creature can't block.
This creature has haste as long as an opponent has 10 or less life.
Landfall — Whenever a land you control enters, you may return this card from your graveyard to the battlefield.

Rise of the Dark Realms

Put all creature cards from all graveyards onto the battlefield under your control.

Zendikar's Roil

Landfall — Whenever a land you control enters, create a 2/2 green Elemental creature token.

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.

The Ring Goes South

The Ring tempts you. Then reveal cards from the top of your library until you reveal X land cards, where X is the number of legendary creatures you control. Put those land cards onto the battlefield tapped and the rest on the bottom of your library in a random order.

Lion's Eye Diamond

Discard your hand, Sacrifice this artifact: Add three mana of any one color. Activate only as an instant.

Fractured Powerstone

{T}: Add {C}.
{T}: Roll the planar die. Activate only as a sorcery.

Sméagol, Helpful Guide

At the beginning of your end step, if a creature died under your control this turn, the Ring tempts you.
Whenever the Ring tempts you, target opponent reveals cards from the top of their library until they reveal a land card. Put that card onto the battlefield tapped under your control and the rest into their graveyard.

Sol Talisman

Suspend 3—{1} (Rather than cast this card from your hand, pay {1} and exile it with three time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)
{T}: Add {C}{C}.

Uruk-hai Berserker

When this creature enters, the Ring tempts you.

Accursed Marauder

When this creature enters, each player sacrifices a nontoken creature of their choice.

Fellwar Stone

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

Ob Nixilis, the Fallen

Landfall — Whenever a land you control enters, you may have target player lose 3 life. If you do, put three +1/+1 counters on Ob Nixilis.

Mirrormere Guardian

When this creature dies, the Ring tempts you.

Enraged Huorn

Trample
When this creature enters, the Ring tempts you.

Moss Diamond

This artifact enters tapped.
{T}: Add {G}.

Lotus Bloom

Suspend 3—{0} (Rather than cast this card from your hand, pay {0} and exile it with three time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)
{T}, Sacrifice this artifact: Add three mana of any one color.

Greensleeves, Maro-Sorcerer

Protection from planeswalkers and from Wizards
Greensleeves's power and toughness are each equal to the number of lands you control.
Landfall — Whenever a land you control enters, create a 3/3 green Badger creature token.

The Black Breath

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

Sporemound

Landfall — Whenever a land you control enters, create a 1/1 green Saproling creature token.

Dúnedain Rangers

Landfall — Whenever a land you control enters, if you don't control a Ring-bearer, the Ring tempts you.

Bombadil's Song

Target creature you control gets +1/+1 and gains hexproof until end of turn. The Ring tempts you. (A creature with hexproof can't be the target of spells or abilities your opponents control.)

Arcane Signet

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

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.

Claim the Precious

Destroy target creature. The Ring tempts you.

Talisman of Resilience

{T}: Add {C}.
{T}: Add {B} or {G}. This artifact deals 1 damage to you.

Sam's Desperate Rescue

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

Elvish Spirit Guide

Exile this creature from your hand: Add {G}.

Golgari Signet

Mind Stone

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

Lotus Petal

{T}, Sacrifice this artifact: Add one mana of any color.

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.

Elfsworn Giant

Reach (This creature can block creatures with flying.)
Landfall — Whenever a land you control enters, create a 1/1 green Elf Warrior creature token.

Chrome Mox

Imprint — When this artifact enters, you may exile a nonartifact, nonland card from your hand.
{T}: Add one mana of any of the exiled card's colors.