msem-instigator

({T}: Add {B}.)
Wanderlust — Otherworldly Swamp enters tapped unless you control four or more other differently named lands.
{1}, {T}: Add one mana of any color.

As long as it's your turn, Ameret is a 4/4 Angel creature with flying, haste, indestructible, and “Whenever Ameret attacks, attach any number of Equipment you control to them.”
[+2]: Create two 1/1 red and white Cleric creature tokens with lifelink.
[–3]: Ameret deals 4 damage to target creature or planeswalker. You gain 4 life.
[–4]: For each creature you control, create a Weapon token and attach it to that creature. (It's an Equipment artifact with equip {2} and “Equipped creature gets +1/+1.”)

Look at the top three cards of your library. You may reveal an instant or sorcery card from among them and put it into your hand. Put the rest on the bottom of your library in any order.

When Gilded Yak enters, you gain 3 life.

Vigilance
When Tortle Guard enters, it explores. (Reveal the top card of your library. Put it into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then you may put that card in your graveyard.)

Target creature gets +1/+5 until end of turn.
Draw a card.

Search your library for a card. You may cast it without paying its mana cost if it's a green creature or Revelation spell with mana value X or less. Then shuffle.
Coalesce {X}{X}{G}{G}{G}{G} (You may cast this from your graveyard for {X}{X}{G}{G}{G}{G}. If you do, it enters as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)

Casualty of War deals 4 damage to target creature or planeswalker.
{2}{R}{R}, Exile Casualty of War from your graveyard: Arm up to two target creatures you control. Activate only as a sorcery. (Create a colorless Equipment artifact token with “Equipped creature gets +1/+0” and equip {2}, then attach it to that creature.)

Menace
Once during each of your turns, when you sacrifice a permanent, you may put a +1/+1 counter on Assimilated Runner.

Protection from noncreatures and from creatures with power 3 or less
Players dealt damage by Absurdity also get that many poison counters. (A player with ten or more poison counters loses the game.)
When Absurdity is put into a graveyard from anywhere, shuffle it into its owner's library.

Flying
{R}: Volatile Elemental gets +1/+0 until end of turn.

Hafiq the Wise has hexproof as long as you've cast a spell this turn.
{U}, Discard a card with mana value X: Counter target spell with mana value X.
{U}, Sacrifice another permanent with mana value X: Return target instant or sorcery card with mana value X from your graveyard to your hand.

Improve {1}{R} ({1}{R}: 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.)
When Siegebreaker Ogre enters, create two 1/1 red Goblin creature tokens with haste.

Menace
Whenever Aswaran Conquerer attacks, you may sacrifice a nonland permanent. If you do, creatures you control get +1/+1 and gain trample until end of turn.

Menace, haste
Whenever another player casts a spell that targets Plasma Addict, that player gains control of Plasma Addict.

Bleed {R} (You may cast this spell for its bleed cost if an opponent has lost life this turn.)
Amongst the Flames deals 2 damage to each creature.

You may play cards you own from outside the game.

Whenever Single-Minded Mob becomes untapped, it gets +2/+2 until end of turn.

Wu Xing (Add effects based on the number of colors of mana spent to cast this spell.)
1 | Counter target permanent spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.
3 | You gain life equal to its mana value.

Resolute — Skerry Serpent must be blocked if able as long as its power is greater than its base power.

Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
At the beginning of combat on your turn, if you control three or more creatures, Traveling Scholar gets +1/+0 until end of turn.

({T}: Add {B} or {R}.)
Molten Falls enters tapped.
{1}, {T}: Add {B}{B} or {R}{R}.

At the beginning of each end step, you gain X life and each opponent loses X life, where X is the number of times you gained life this turn.
{2}{B}: Darksand Acolyte gains indestructible and lifelink until end of turn.

When Evolving Elemental enters, scry 3, then reveal the top card of your library. Put a number of +1/+1 counters on Evolving Elemental equal to that card's mana value.

Target creature you control becomes a copy of another target creature you control until end of turn.
Showcase {2}{U}{U} (Then if you cast this for its showcase cost, create a 1/1 red Bard creature token that can't block and exile this. Whenever it attacks, you may cast a free copy of this.)