msem-instigator

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.

Flash
When Seabreen Nullmage enters, counter target activated or triggered ability. (A triggered ability uses the words “when,” “whenever,” or “at”. Mana abilities can't be targeted.)

Flying
Other Pirates you control get +1/+1.
Whenever one or more other Pirates you control deal combat damage to a player, forebode. (Create a tapped colorless Omen artifact token with “{T}, Discard a card, Sacrifice this artifact: Draw a card.”)

Target creature gets +2/+2 until end of turn. Whenever that creature deals combat damage to a player or planeswalker this turn, draw that many cards.

Reach
Knotweald Ranger can't block creatures without flying.

Whenever you sacrifice another permanent, Fretport Mob gets +1/+1 and gains haste until end of turn.

Trample, haste
Whenever Lisseria, General of Kanaa attacks, you may exchange its power with the power of target creature defending player controls until end of turn.

Vigorbreath Scourge enters with X +1/+1 counters on it.
Whenever Vigorbreath Scourge attacks, it gets +X/+X until end of turn, where X is your devotion to green. Then if its power is 6 or greater, draw a card. (Each {G} in the mana costs of permanents you control counts toward your devotion to green.)

When Writhing Gateway enters, you may discard a card. If you do, create a 5/3 black Horror creature token.
{1}{B}{B}, Discard a card: Create a 5/3 black Horror creature token.

{T}: Draw a card, then discard a card.

Players can't gain life.
At the beginning of each player's upkeep, if that player has 10 or less life, they lose 1 life.

Until end of turn, target creature you control gains “When this creature dies, return it to the battlefield under your control with a +1/+1 counter on it.”

[+1]: Distribute two +1/+1 counters among up to two target creatures. You gain 2 life.
[–1]: Create a 2/2 green Cat Warrior creature token.
[–3]: Exile target creature. Its controller may search their library for a basic land card, put it onto the battlefield tapped, then shuffle.
[–7]: You get an emblem with “Creatures you control get +X/+X, where X is your life total.”

Hexproof from mana value 3 or less
{W}: Rhysta of the Roses gains lifelink until end of turn.
{B}: Rhysta of the Roses gains menace until end of turn.

Counter target noncreature spell. Investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Flying
Spells your opponents cast cost an additional 2 life to cast.

Chigau Market Outskirts enters tapped. When it does, choose a creature card name.
{T}: Add {B}.
{1}, {T}, Sacrifice Chigau Market Outskirts: You may cast a creature spell with the chosen name from your graveyard this turn.

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.

Archive 3 (As this enters, shuffle the top three cards of your main library into a new face up library. Sacrifice this after the archived library is empty.)
{T}: Add {C}.
{1}, {T}: Scry 1.

Survivors you control get +2/+2.

Archive 5 (As this enters, shuffle the top five cards of your main library into a new face up library. Sacrifice this after the archived library is empty.)
Once during each combat phase, you may cast the top card of the archived library as though it had flash.

Exile the top card of your library. You may play that card this turn.
Flashback {1}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Menace

Flying (This creature can't be blocked except by creatures with flying or reach.)
When Drake Youngling enters, draw a card.

Mark (Whenever this creature attacks, mark target creature until end of turn.)
Undercity Diplomat can't be blocked by marked creatures.