msem-instigator

Detain target creature. (Until your next turn, that creature can't attack or block and its activated abilities can't be activated.)
Scry 1.

When Mana Rose enters, you gain 2 life and scry 2.
{1}, {T}: Add one mana of any color.

Counter target spell unless its controller pays {2}.
Wanderlust — If that spell has mana value 2 or less and you control four or more differently named lands, counter that spell.

Prowess
Whenever Outsider Alchemist deals combat damage to a player, create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)

Hymn of Fury deals 1 damage to each creature, then each creature you control gains haste and double strike until end of turn.

Destroy target artifact or land.

For each permanent type, return up to one target card of that type from your graveyard to your hand. (The permanent types are artifact, creature, enchantment, land, and planeswalker.)

Whenever you cast a spell, if mana from an artifact was spent to cast it, exile the top card of your library. You may play that card until you exile another card with Savant of Cables.

When Coercive Cardinal enters, choose an opponent. That player may have you gain 5 life. If the player doesn't, create two 1/1 white Cleric creature tokens.

Whenever you cast a black spell, you lose 1 life.

When Moth-Heart Husk dies, create a 1/1 black Spirit creature token with flying.
Revive {3}{B} ({3}{B}, Exile this card from your graveyard: Create a token that's a copy of this card, except it has no mana cost. Activate this ability only any time you could cast a sorcery.)

Flying
Whenever an opponent discards a card, you may exile it. If you do, create a 1/1 black Bird creature token with flying and “This creature can't block.”
{B}, Sacrifice three Birds: You may cast a card exiled with Krahen, Dusk's Call without paying its mana cost.

Menace
Whenever you cast a spell from your graveyard, The Selhoff Twins deals damage equal to that spell's mana value to any target. Then copy that spell. You may choose new targets for the copy. (A copy of a permanent spell becomes a token.)

This spell costs {1} less to cast if you have more life than an opponent and {1} less to cast if you control a Cleric.
Deathtouch

Aura and Equipment spells you cast cost {1} less to cast.

Other creatures get -1/-1.
Recite {1}{B} (You may cast this creature from your graveyard for its recite cost. If you do, exile it when it enters or if it would leave the battlefield.)

Permanents you control with mana value 1 or less have first strike, haste, and lifelink.

{T}: Add {C}.
{T}, Pay 1 life: Add {U} or {R}.

Reveal the bottom card of your library. You may put it on top of your library. Target creature gets -0/-X until end of turn, where X is that card's mana value.

Gain control of target artifact or creature until end of turn. Untap it. It gains haste until end of turn.

[+2]: Destroy up to one target monocolored permanent.
[–3]: Create an 8/8 Elemental creature token with flying, first strike, vigilance, trample, and lifelink that's all colors.
[–5]: Draw three cards. You pay {0} rather than pay the mana cost for the next spell you cast this turn.

Whenever you activate a loyalty ability of Reyhsia, Truth Chaser, you may exile a card from your hand. If you do, draw a card.
[+2]: Each player exiles up to two cards from their hand, then draws that many cards.
[0]: Until end of turn, you may play a card exiled with Reyhsia and you may spend mana as though it were mana of any color to cast that spell.
[–10]: Each player exiles all but the bottom card of their library and may play cards they own exiled this way until the end of their next turn.

Motley — At the beginning of combat on your turn, if there are five or more names among nonland permanents you control, Ochre Knight gets +2/+1 until end of turn and you gain 1 life.

Advance {1}{B} (Cast this for {1}{B} to advance it as it enters. {1}{B}: Advance this as a sorcery.)
Whenever Scarcrawler advances, you lose life equal to its power, then put a +1/+1 counter on it.

Guang Shrine enters tapped.
{T}: Add {G} or {W}.
{G/W}, {T}, Sacrifice Guang Shrine: Put a +1/+1 counter on target creature you control. Activate only as a sorcery.