msem-instigator

Whenever a storied permanent you control enters, tap target creature an opponent controls. (Enchantments and legendary permanents are storied.)

{T}, Pay 1 life: Add {G} or {U}.
{2}, {T}, Sacrifice Alchemist's Laboratory and another permanent: Draw a card. Activate only during your turn.

Return up to one target creature card with mana value 1 or less from your graveyard to the battlefield.

{T}: Add {C}.
{T}: Add one mana of any color. Activate only if you control a creature with a +1/+1 counter on it.

{1}, Sacrifice a creature: Put a +1/+1 counter on Implant Scavenger and move any +1/+1 counters from the sacrificed creature onto it. It gains menace until end of turn.

Equipped creature gets +2/+2 and has protection from white and from blue.
Whenever equipped creature deals combat damage to a player, until your next turn, spells that player casts cost {1} more to cast and spells you cast cost {1} less to cast.
Equip {2}

Ancient Cairns enters tapped.
As Ancient Cairns enters, choose a color other than red.
{T}: Add {R} or one mana of the chosen color.

Whenever a creature attacks you or a planeswalker you control, put that creature on the bottom of its owner's library unless its controller pays {2}.

When Captured Mind dies, create a 3/3 white Construct enchantment creature token.

When Fabled Chishou enters, create a token that's a copy of it, except it doesn't have this ability.
At the beginning of each end step, if Fabled Chishou isn't in a pack, sacrifice it. (Two or more creatures you control with equal power are in a pack.)

Ravenous Grue enters with a menace counter on it.
{5}{B}{B}, Remove a menace counter from Ravenous Grue: Destroy target creature.

{1}, Sacrifice another creature: Put a +1/+1 counter on Dread Cabalist and on up to one target legendary creature. Activate only as a sorcery.

Abyss Howler must be blocked if able.
Whenever Abyss Howler becomes blocked, defending player loses 2 life and you gain 2 life.

Wanderlust — This spell has flash as long as you control four or more differently named lands.
Draw four cards.

Breach (Whenever this deals combat damage to a player, you may have it become an Aura Curse until your next turn. Attach it to that player.)
Once each turn, when a Curse you control becomes attached to an opponent, you may sacrifice it. If you do, reveal cards from the top of your library until you reveal a Curse card. Put that card onto the battlefield attached to that player, and the rest on the bottom of your library in a random order.

Search your library for a basic land card, reveal it, put it into your hand, then shuffle. Scry 2.

Whenever a Survivor you control dies, target creature you don't control gets -1/-1 until end of turn.

Flying
At the beginning of your end step, up to one other target creature you control voyages. (If it isn't blocking or targeted by another spell or ability, it phases out.)
Whenever a creature you control phases in, you may have it become a copy of target creature you control until end of turn.

When Irticull's Vanguard enters, exile target nonland permanent an opponent controls until Irticull's Vanguard leaves the battlefield.
Reprocess {1}{W}{W}{W} (Cast a copy of this from your graveyard by exiling it and paying {1}{W}{W}{W}. Spend only mana from differently named sources this way.)

(As an Encounter enters, choose an opponent to protect it. You and others can attack it. When defense counters are removed, create a 0/0 Army token if you don't control one, then put that many +1/+1 counters on a Army you control.)
When Crisis in Nizev enters, exile the top three cards of your library. Until the end of your next turn, you may play those cards.

Return target nonland permanent to its owner's hand. If you control an Elemental, draw a card.

Sacrifice a creature: Pale Horse gets +2/+2 until end of turn.
Ride {B} ({B}: Transform this and attach it to target creature you control without a Steed. Ride only as a sorcery.)

{T}, Pay 1 life: Add {G} or {U}.
{1}, {T}, Sacrifice Hidden Hollow: Investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

As an additional cost to cast this spell, exile two cards from your graveyard with the same mana value.
Search your library for a card with the same mana value as the exiled cards, reveal it, put it into your hand, then shuffle.