msem-instigator

{1}{G}: Keen Seafarer voyages. (If it isn't blocking or targeted by another spell or ability, it phases out.)
Whenever Keen Seafarer phases in, put a +1/+1 counter on it.

Trample
Frontier Hoof gets +1/+1 for each other Centaur you control.

Whenever one or more +1/+1 counters are put on a creature you control, you may search your library for a creature card, reveal it, put it into your hand, then shuffle.

You gain 3 life.
Draw a card.

This spell costs {2} less to cast if you've cast another spell this turn.
Draw two cards, then put a card from your hand on top of your library.

Flash

You gain 3 life.
Amass Soldiers 1. (Put a +1/+1 counter on an Army you control. It's also a Soldier. If you don't control one, create an 0/0 black Soldier Army creature token first.)

Deathtouch
Mirage {1}{B} (You may cast this spell as though it had flash for its mirage cost. If you do, sacrifice it at the beginning of the next cleanup step.)

Creatures you control have haste.
{4}{R}: Until end of turn, gain control of target creature an opponent controls without a vision counter on it. Untap that creature and put a vision counter on it. Activate only as a sorcery.

When Lustrebloom Diviner enters, create a Treasure token.
At the beginning of each end step, if you spent three or more colors of mana to cast spells this turn, you gain 3 life. If you spent {W}{U}{B}{R}{G}, draw a card.

Flying
Legendary spells you cast cost {1} less to cast.
{W}{U}{B}{R}{G}: Search your library or graveyard for a legendary card, reveal that card, and put it into your hand. If you searched your library this way, shuffle.

When Shadowstrider dies, create a 2/2 colorless Spirit creature token.

Flying, trample
When Whisper in the Rift enters, target player mills half their library, rounded down.
When Whisper in the Rift dies, you may cast up to two instant, sorcery, and/or creature cards from among opponent's graveyards without paying their mana cost.

Draw two cards.
Cycling {2} ({2}, Discard this card: Draw a card.)

Enchant creature
Enchanted creature gets +2/+1 and has flying.
Foresight — Whenever you draw your second card each turn, return Sphinx's Sight from your graveyard to your hand.

When Depthlight Brute enters, if you control three or more artifacts, each opponent loses 3 life and you gain 3 life.

Each opponent sacrifices a creature that dealt damage this turn. You gain 2 life, then abound. (To abound, you may cast a spell that costs less than this from your hand without paying its mana cost.)

When Chamber of Penance enters, exile target nonland permanent an opponent controls until Chamber of Penance leaves the battlefield.

Enchant creature
Enchanted creature gets +2/+1 and has “Whenever this creature attacks, target creature an opponent controls can't block this turn.”

When Eyes of the Maghbri enters, if you control a creature token, create a 2/2 black Hound creature token.

{2}{B}, {T}, Discard a card: Create a 2/2 black Zombie creature token. If a noncreature card was discarded this way, that token enters tapped.

At the beginning of each opponent's end step, if no spells controlled by that player resolved this turn, create a 1/1 blue Illusion creature token with “This gets +1/+1 for each other Illusion you control.”

Scoured Mesa enters tapped.
{T}: Add {W}.
Desertcycling {1}{W} ({1}{W}, Discard this card: Search your library for a Desert card, reveal it, and put it into your hand, then shuffle.)

Creatures you control get +1/+1 and gain trample until end of turn.
Fuse (You may cast one or both halves of this card from your hand.)

{2}{U}: Target creature can't be blocked this turn.