Selesnya Sanctuary

Selesnya Sanctuary enters tapped.
When Selesnya Sanctuary enters, return a land you control to its owner's hand.
{T}: Add {G}{W}.

Frodo Baggins

Whenever Frodo Baggins or another legendary creature you control enters, the Ring tempts you.
As long as Frodo is your Ring-bearer, it must be blocked if able.

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.)

Noble Hierarch

Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
{T}: Add {G}, {W}, or {U}.

Plains

Inherited Envelope

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

Hamza, Guardian of Arashin

This spell costs {1} less to cast for each creature you control with a +1/+1 counter on it.
Creature spells you cast cost {1} less to cast for each creature you control with a +1/+1 counter on it.

Forest

Samwise the Stouthearted

Flash
When Samwise the Stouthearted enters, choose up to one target permanent card in your graveyard that was put there from the battlefield this turn. Return it to your hand. Then the Ring tempts you.

Aragorn, Company Leader

Whenever the Ring tempts you, if you chose a creature other than Aragorn, Company Leader as your Ring-bearer, put your choice of a counter from among first strike, vigilance, deathtouch, and lifelink on Aragorn.
Whenever you put one or more counters on Aragorn, put one of each of those kinds of counters on up to one other target creature.

Whisperer of the Wilds

{T}: Add {G}.
Ferocious — {T}: Add {G}{G}. Activate only if you control a creature with power 4 or greater.

Slip On the Ring

Exile target creature you own, then return it to the battlefield under your control. The Ring tempts you.

Mirror Box

The "legend rule" doesn't apply to permanents you control.
Each legendary creature you control gets +1/+1.
Each nontoken creature you control gets +1/+1 for each other creature you control with the same name as that creature.

Wooded Bastion

{T}: Add {C}.
{G/W}, {T}: Add {G}{G}, {G}{W}, or {W}{W}.

Andúril, Narsil Reforged

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
Whenever equipped creature attacks, put a +1/+1 counter on each creature you control. If you have the city's blessing, put two +1/+1 counters on each creature you control instead.
Equip {3}

Mikaeus, the Lunarch

Mikaeus, the Lunarch enters with X +1/+1 counters on it.
{T}: Put a +1/+1 counter on Mikaeus.
{T}, Remove a +1/+1 counter from Mikaeus: Put a +1/+1 counter on each other creature you control.

Ajani, the Greathearted

Creatures you control have vigilance.
+1: You gain 3 life.
−2: Put a +1/+1 counter on each creature you control and a loyalty counter on each other planeswalker you control.

Now for Wrath, Now for Ruin!

Put a +1/+1 counter on each creature you control. They gain vigilance until end of turn. The Ring tempts you.

Plaza of Heroes

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a legendary spell.
{T}: Add one mana of any color among legendary permanents you control.
{3}, {T}, Exile Plaza of Heroes: Target legendary creature gains hexproof and indestructible until end of turn.

Shortcut to Mushrooms

When Shortcut to Mushrooms 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.

Delighted Halfling

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

Byrke, Long Ear of the Law

Vigilance
When Byrke, Long Ear of the Law enters, put a +1/+1 counter on each of up to two target creatures.
Whenever a creature you control with a +1/+1 counter on it attacks, double the number of +1/+1 counters on it.

Tolsimir Wolfblood

Other green creatures you control get +1/+1.
Other white creatures you control get +1/+1.
{T}: Create Voja, a legendary 2/2 green and white Wolf creature token.

Kenrith, the Returned King

{R}: All creatures gain trample and haste until end of turn.
{1}{G}: Put a +1/+1 counter on target creature.
{2}{W}: Target player gains 5 life.
{3}{U}: Target player draws a card.
{4}{B}: Put target creature card from a graveyard onto the battlefield under its owner's control.

Temple of Plenty

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {G} or {W}.

Sovereign Okinec Ahau

Ward {2}
Whenever Sovereign Okinec Ahau attacks, for each creature you control with power greater than that creature's base power, put a number of +1/+1 counters on that creature equal to the difference.

Mithril Coat

Flash
Indestructible
When Mithril Coat enters, attach it to target legendary creature you control.
Equipped creature has indestructible.
Equip {3}

Relic of Legends

{T}: Add one mana of any color.
Tap an untapped legendary creature you control: Add one mana of any color.