Wonder

Flying
As long as Wonder is in your graveyard and you control an Island, creatures you control have flying.

Death Frenzy

All creatures get -2/-2 until end of turn. Whenever a creature dies this turn, you gain 1 life.

Havengul Lich

{1}: You may cast target creature card in a graveyard this turn. When you cast it this turn, Havengul Lich gains all activated abilities of that card until end of turn.

Sultai Ascendancy

At the beginning of your upkeep, surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Sidisi's Pet

Lifelink (Damage dealt by this creature also causes you to gain that much life.)
Morph {1}{B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Sidisi, Brood Tyrant

Whenever Sidisi, Brood Tyrant enters or attacks, mill three cards.
Whenever one or more creature cards are put into your graveyard from your library, create a 2/2 black Zombie creature token.

Opulent Palace

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

Muldrotha, the Gravetide

During each of your turns, you may play a land and cast a permanent spell of each permanent type from your graveyard. (If a card has multiple permanent types, choose one as you play it.)

Taigam, Sidisi's Hand

Skip your draw step.
At the beginning of your upkeep, look at the top three cards of your library. Put one of them into your hand and the rest into your graveyard.
{B}, {T}, Exile X cards from your graveyard: Target creature gets -X/-X until end of turn.

Sidisi's Faithful

Exploit (When this creature enters, you may sacrifice a creature.)
When Sidisi's Faithful exploits a creature, return target creature to its owner's hand.

Sidisi, Undead Vizier

Deathtouch
Exploit (When this creature enters, you may sacrifice a creature.)
When Sidisi, Undead Vizier exploits a creature, you may search your library for a card, put it into your hand, then shuffle.