msem-instigator

{T}: Add {W} or {B}.
{T}, Sacrifice Sigil of Martyrdom: Add {W}{B}.

When Silence Dissent enters, each player exiles a card from their hand at random until Silence Dissent leaves the battlefield.
{1}{W}: Exile Silence Dissent. Return it to the battlefield under your control at the beginning of your next end step.

Counter target spell unless its controller pays {1} and 3 life.

Tribute 4 (As this creature enters, an opponent of your choice may put four +1/+1 counters on it.)
When Slaughter enters, if tribute was paid, destroy all other creatures. Otherwise, destroy all creatures you don't control.

Slipsand Oasis enters tapped unless you played it from exile.
{T}: Add {W} or {B}.

Solemn Bastion enters tapped. When it enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
{T}: Add {W} or {B}.

Somber Meadow enters tapped.
{T}: Add {W} or {B}.
{1}, {T}: Add one mana of any color.

Whenever another creature you control enters, target opponent loses 1 life and you gain 1 life.
Sacrifice Somber River Bearer: Creatures you control gain indestructible until end of turn.

Soul of Misery gets +1/+1 as long as you control a Swamp.
{4}{B}: Target player discards a card. Activate only as a sorcery.

Flying
Whenever another creature you control dies, creatures you control get +1/+1 until end of turn.

Whenever Stargaze Spirit or another creature dies, you may gain 1 life.
Revive {3}{W} ({3}{W}, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

You gain life equal to the number of creatures you control.
Each opponent loses life equal to the number of creatures they control.
Destroy all creatures, then exile all graveyards.

Syurrai Traitor gets +1/+1 as long as you control a Plains.
{3}{W}: Create a 1/1 white Soldier creature token.

First mate—Your starting deck contains no more than eight cards of each nonland card type. (If this card outside the game is your chosen first mate, you may swap it with a card in your opening hand.)
Lifelink
At the beginning of your upkeep, you may pay 3 life. If you do, exile another target nonland permanent until Tabia leaves the battlefield. If you control another permanent that shares a card type with it, exile it instead.

Each player sacrifices a creature with the highest power among creatures they control and a creature with the lowest power among creatures they control.

At the beginning of the next end step, create X 1/1 white Spirit creature tokens with flying, where X is the number of creatures that died this turn.
Reconstruct {2}{W}{B} (You may cast this from your graveyard for its reconstruct cost reduced by the mana value of a permanent you sacrifice as you cast it this way. Then exile this.)

I — Exile target creature an opponent controls until The Banishment of Seh'a leaves the battlefield.
II — Exile up to three cards from target opponent's graveyard.
III — You gain life equal to the number of cards in exile.

Codex — Out-of-Body Experience; Event Horizon; Strike from the Shadows; Second Death; Anguished Unmaking. (As this enters, conjure its contents into a shuffled face-up additional library.)
You can't draw from this codex's library.
Whenever a creature you control dies, put a card from this codex's library into your hand.

At the beginning of your end step, create a 1/1 colorless Human creature. Put a sacrifice counter on it.
Creature tokens you control with sacrifice counters on them can't attack or block and have “Sacrifice this creature: Add {C}.”

Primal {5}{W}{B} (During your turn, you may cast this spell for {5}{W}{B} instead of playing a land.)
Destroy all creatures. If this spell was cast for its primal cost, for each player, put up to one creature card from that player's graveyard onto the battlefield under your control.

Each player sacrifices a creature with mana value X or greater.
Return up to one target creature card with mana value X or less from your graveyard to the battlefield.

Return target creature card from your graveyard to the battlefield.

Experience (Whenever this creature attacks, if it has fewer than three +1/+1 counters on it, put a +1/+1 counter on it.)
{1}{W}, Sacrifice a creature or enchantment: Scry 1, then draw a card. Activate only if Trauma Surgeon has a +1/+1 counter on it.

Whenever you cast an Aura spell, put two +1/+1 counters on Traveling Thespians.

Tsubasa's Redoubt enters tapped.
When Tsubasa's Redoubt enters, you may mill two cards.
{T}: Add {W} or {B}.