msem-instigator

Dawn Hill Swiftstriker gets +2/+0 as long as you control another Warrior.

({T}: Add {G} or {W}.)
Wandering Hamlet enters tapped unless you control two or more basic lands.

Whenever Determined to Prevail or another artifact or enchantment you control enters, target creature you control gets +1/+1 and gains indestructible and vigilance until end of turn.

Harmony — Target creature gains haste until end of turn.
When Streetside Entertainer enters, harmonize. (Trigger up to one harmony of one permanent you control.)

When Lifebreather enters, you gain 4 life.
Revive {4}{W} ({4}{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.)

Flash
If one or more counters would be put on a creature you control, put that many plus one of each of those kinds of counters on that creature instead.

Whenever Shifty Fink attacks, if you have more cards in hand than defending player, it gets +2/+1 until end of turn.

This spell costs {1} less to cast for each other spell you've cast this turn.

You may cast instant and sorcery cards from your graveyard. Spend no more than one mana of each color to cast spells this way each turn. If a spell cast this way would be put into your graveyard, exile it instead.

Improve {B} ({B}: Put a +1/+1 counter on this creature. This costs {1} more to activate for each +1/+1 counter on it. Improve only as a sorcery.)
Whenever a nontoken creature you control dies, if it was embattled, you may pay {B}. If you do, create a 2/2 black Zombie creature token. (A creature is embattled if it has a counter on it or has a permanent you control attached to it.)

When Miede-District Alchemist enters, add {R}{R}{R}.
Paranoia {1}{R} (You may cast this spell for its paranoia cost when a permanent you control leaves the battlefield.)

When Diasune Irregular enters, if you control another Warrior, draw a card.

Create X 1/1 blue Boar Dragon creature tokens with flying. (Then exile this card. You may cast the creature later from exile.)

Scorch deals 3 damage to any target.

Whenever two or more creatures you control deal combat damage to a player, you gain 3 life and create a Treasure token. (It's an artifact with “{T}, Sacrifice this permanent: Add one mana of any color.”)
Whenever you sacrifice your second permanent each turn, you draw a card and you lose 1 life.

Equipped creature gets +1/+1 and has flying.
Equip {2}

[+1]: Each player discards a card or sacrifices a creature.
[–3]: Vikalden deals X damage to any target and you gain X life, where X is the number of Swamps you control.
[–5]: You get an emblem with “{B}, Pay 2 life: Draw a card.”

Search your library for a permanent card with mana value 3 or less and put it onto the battlefield, then shuffle.
Motley — Then if there are five or more names among nonland permanents you control, you gain 7 life.

All creatures get -2/-2 until end of turn.
Metamorph {1}{B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up and cast it at any time for its metamorph cost.)

{T}: Add {C}.
{T}, Pay 1 life: Add {U}.
{4}{U}, {T}, Sacrifice Verdant Oasis: Draw two cards. Activate only as a sorcery.

Enchant creature you control
When Erebos's Benefaction enters, scry 2.
Enchanted creature gets +2/+2 and has menace.

Target creature gets +2/+2 until end of turn. If you control four or more lands, that creature gets an additional +2/+2 until end of turn.

(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 Dawn Over Soli enters or is defeated, look at the top five cards of your library. Put up to one creature card with mana value 2 or less from among them onto the battlefield. Put the rest on the bottom of your library in a random order.

Death knell — Put a trample counter on target creature you control. (As a creature you control dies, trigger one death knell of that creature or another permanent you control.)
Sacrifice a creature: Put a +1/+1 counter on Crushing Victor. Activate only as a sorcery.

({T}: Add {U}.)
Aerie's Pillar enters tapped.
Flying
{2}{U}{U}: Aerie's Pillar becomes a creature in addition to its other types until end of turn.