Taigam, Ojutai Master

Instant, sorcery, and Dragon spells you control can't be countered.
Whenever you cast an instant or sorcery spell from your hand, if Taigam, Ojutai Master attacked this turn, that spell gains rebound. (Exile the spell as it resolves. At the beginning of your next upkeep, you may cast that card from exile without paying its mana cost.)

Mirror-Mad Phantasm

Flying
{1}{U}: Mirror-Mad Phantasm's owner shuffles it into their library. If that player does, they reveal cards from the top of that library until a card named Mirror-Mad Phantasm is revealed. The player puts that card onto the battlefield and all other cards revealed this way into their graveyard.

Disallow

Counter target spell, activated ability, or triggered ability. (Mana abilities can't be targeted.)

Necrotic Ooze

As long as Necrotic Ooze is on the battlefield, it has all activated abilities of all creature cards in all graveyards.

Laboratory Maniac

If you would draw a card while your library has no cards in it, you win the game instead.

Dig Through Time

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Look at the top seven cards of your library. Put two of them into your hand and the rest on the bottom of your library in any order.

Elixir of Immortality

{2}, {T}: You gain 5 life. Shuffle Elixir of Immortality and your graveyard into their owner's library.

Reliquary Tower

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

Diabolic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Archaeomancer

When Archaeomancer enters, return target instant or sorcery card from your graveyard to your hand.

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.

Azor's Elocutors

At the beginning of your upkeep, put a filibuster counter on Azor's Elocutors. Then if Azor's Elocutors has five or more filibuster counters on it, you win the game.
Whenever a source deals damage to you, remove a filibuster counter from Azor's Elocutors.