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.

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.

Jungle Hollow

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

Sam's Desperate Rescue

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

Dismal Backwater

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

Island

Thornwood Falls

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

Uruk-hai Berserker

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

Forest

Birthday Escape

Opulent Palace

Opulent Palace enters tapped.
{T}: Add {B}, {G}, or {U}.

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.

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.

Elven Farsight

Scry 3, then you may reveal the top card of your library. If it's a creature card, draw a card.

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, Friend of the Shire as your Ring-bearer, draw a card.

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.

Soothing of Sméagol

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

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.