msem-instigator

As Nimble Sandstorm enters, choose speed or power.
At the beginning of combat on your turn,
• Speed — Target creature gains haste until end of turn.
• Power — Target creature gets +2/+0 until end of turn.

When Doomstep Giant enters, each player sacrifices a land.

When Golden Grizzly enters, create an Idol token. (It's an artifact with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)

Lionize {1}{B} ({1}{B}, Exile this card from your hand: Put a +1/+1 counter on target creature and it gains the following ability until end of turn. You may cast this card on a later turn from exile.)
Deathtouch

Whenever Ashen Host becomes the target of a spell, Ashen Host deals 2 damage to any target.

Choose one —
• Counter target spell unless its controller pays {2}.
• Change the target of target spell with a single target unless that spell's controller pays {2}.

Target creature gets +1/+1 and gains indestructible until end of turn.

Trample
When Leyran Alpha enters, create two 2/2 green Wolf creature tokens with haste.
Whenever a creature you control deals damage to an opponent, put a +1/+1 counter on that creature.

Haste
Sandstorm Sentinel enters with X +1/+1 counters on it, where X is your fealty to Deserts. (Each Desert you control counts toward your fealty to Deserts.)
Mirage {1}{R} (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.)

When Sandbluff Barflies enters, you gain 2 life.

Each player searches their library for a basic land card, puts it onto the battlefield tapped, then shuffles.

Equipped creature has “{T}, Sacrifice this creature: Return target creature card from your graveyard to the battlefield.”
Equip {5}
Equip {1}{B}{B}

Converge — Exile up to X nonland permanents you control, where X is the number of colors of mana spent to cast Reenter Orbit, then return them to the battlefield under your control.

When Ontarachie Envoy enters, nourish, then germinate. (To nourish, put a +1/+1 counter on this creature or create a 1/1 white Citizen creature token. To germinate, put a +1/+1 counter on a creature you control or create a 1/1 green Saproling creature token.)

When Carrion Sculptor enters, create a 2/2 black Zombie creature token.
{2}{B}, Sacrifice a creature: Return target creature card from your graveyard to your hand.
{1}{B}, Exile Carrion Sculptor from your graveyard: Create a tapped 2/2 black Zombie creature token.

Whenever you upgrade another creature you control, upgrade Lelin, the Wise. (Give it one of the listed counters it doesn't already have.)
• +1/+1
• Flying
• First strike
• Vigilance
• Lifelink
• Hexproof

Enchant creature
Enchanted creature gets +1/+1 and has vigilance.
{2}{G}: Return Behold the Horizon from your graveyard to your hand.

Flying
{1}{U}: Put Gustscreen Cherub on the bottom of its owner's library.
Morph {1}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Exile target creature if its controller controls more lands than you.
Cycling {2} ({2}, Discard this card: Draw a card.)

Flying
Whenever you attack, create two 1/1 white Human creature tokens that are tapped and attacking. Creatures you control get +1/+1 until end of turn.
Fleeting {2}{W}{W} (You may cast this spell for its fleeting cost. If you do, sacrifice it at the beginning of the next end step.)

As an additional cost to cast this spell, sacrifice an artifact or creature.
Create three 1/1 red Construct creature tokens.

Vigilance, reach
Identity — As long as you control at least two other creatures that share a creature type with Gallord of the Order, other creatures you control get +1/+1 and have first strike.

Whenever you cast an instant or sorcery spell, look at the bottom card of your library. You may manifest it. If you don't, put it into your hand. (To manifest a card, put it onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)

Reach
{1}{B}: Bloomcrawler gains deathtouch until end of turn.

When Endless Trove enters, if it's not a token, each opponent may create a token that's a copy of it.
{T}: Add one mana of any color.