In the Darkness Bind Them

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after IV.)
I, II, III — Create a 3/3 black Wraith creature token with menace. The Ring tempts you.
IV — For each opponent, gain control of up to one target creature that player controls until end of turn. Untap those creatures. They gain haste until end of turn. The Ring tempts you.

Neerdiv, Devious Diver

Whenever Neerdiv, Devious Diver becomes tapped, target player mills cards equal to its power.
Whenever you cast a spell from your graveyard or activate an ability of a card in your graveyard, draw a card and put a +1/+1 counter on Neerdiv.

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Sire of Seven Deaths

First strike, vigilance
Menace, trample
Reach, lifelink
Ward—Pay 7 life.

Green Sun's Zenith

Search your library for a green creature card with mana value X or less, put it onto the battlefield, then shuffle. Shuffle Green Sun's Zenith into its owner's library.