Think Twice

Draw a card.
Flashback {2}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Descent into Avernus

At the beginning of your upkeep, put two descent counters on this enchantment. Then each player creates X Treasure tokens and this enchantment deals X damage to each player, where X is the number of descent counters on this enchantment.

Nelly Borca, Impulsive Accuser

Vigilance
Whenever Nelly Borca attacks, suspect target creature. Then goad all suspected creatures. (A suspected creature has menace and can't block.)
Whenever one or more creatures an opponent controls deal combat damage to one or more of your opponents, you and the controller of those creatures each draw a card.

Trial of a Time Lord

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after IV.)
I, II, III — Exile target nontoken creature an opponent controls until this Saga leaves the battlefield.
IV — Starting with you, each player votes for innocent or guilty. If guilty gets more votes, the owner of each card exiled with this Saga puts that card on the bottom of their library.

Círdan the Shipwright

Vigilance
Secret council — Whenever Círdan enters or attacks, each player secretly votes for a player, then those votes are revealed. Each player draws a card for each vote they received. Each player who received no votes may put a permanent card from their hand onto the battlefield.

Rootha, Mercurial Artist

{2}, Return Rootha to its owner's hand: Copy target instant or sorcery spell you control. You may choose new targets for the copy.

Death's Shadow

This creature gets -X/-X, where X is your life total.

Rottenmouth Viper

As an additional cost to cast this spell, you may sacrifice any number of nonland permanents. This spell costs {1} less to cast for each permanent sacrificed this way.
Whenever this creature enters or attacks, put a blight counter on it. Then for each blight counter on it, each opponent loses 4 life unless that player sacrifices a nonland permanent of their choice or discards a card.

A Good Thing

Spells and abilities you control can't destroy, exile, target, or cause you to sacrifice A Good Thing.
At the beginning of your upkeep, double your life total. Then, if you have 1,000 or more life, you lose the game.

Force of Will

You may pay 1 life and exile a blue card from your hand rather than pay this spell's mana cost.
Counter target spell.

Devil K. Nevil

Haste
When Devil K. Nevil enters, jump it over any number of creatures. If it clears those creatures, put that many +1/+1 counters on it. (You can see a jumping demonstration at DevilKNevil.com.)

Zimone, Quandrix Prodigy

{1}, {T}: You may put a land card from your hand onto the battlefield tapped.
{4}, {T}: Draw a card. If you control eight or more lands, draw two cards instead.

Clash of Realities

All Spirits have "When this permanent enters, you may have it deal 3 damage to target non-Spirit creature."
Non-Spirit creatures have "When this creature enters, you may have it deal 3 damage to target Spirit creature."

Avacyn, Angel of Hope

Flying, vigilance, indestructible
Other permanents you control have indestructible.

Ring Out

Counter target noncreature spell.
Whenever an opponent casts a spell named Sol Ring, if Ring Out is in your library, you may search you library for Ring Out, and cast it without paying its mana cost targeting that Sol Ring, then shuffle.