msem-instigator

Whenever you cast an enchantment spell, create a 1/1 white and black Bird creature token with flying and vigilance.
Whenever three or more creatures you control deal combat damage to a player, that player sacrifices a creature. If they can't, they discard a card.

Other Knight creatures you control get +1/+1.

When Confident Traveler dies, create a 1/1 white Human creature token. If Confident Traveler was sacrificed, create two of those tokens instead.

When Confine to the Oasis enters, exile target nonland permanent an opponent controls until Confine to the Oasis leaves the battlefield.
Whenever an opponent casts a spell, put a searching counter on Confine to the Oasis for each of that card's colors. Then if there are ten or more searching counters on Confine to the Oasis, sacrifice it and you gain 3 life.

When Confining Priest enters, exile another target creature with power 4 or less an opponent controls until Confining Priest leaves the battlefield. (That creature returns under its owner's control.)

Flying
At end of combat on your turn, untap all creatures you control with power greater than their base power.

Vigilance
Conflict Capturer gets +2/+0 as long as a permanent you controlled left the battlefield this turn.

When Conflux Ravager enters, destroy target nonland permanent an opponent controls.
Cycling {2} ({2}, Discard this card: Draw a card.)

Whenever you cast an Aura spell, nourish 1. (To nourish 1, either put a +1/+1 counter on this creature or create a 1/1 white Citizen creature token.)

When Conquerer's Blade enters, create a 1/1 white Soldier creature token and attach Conquerer's Blade to it.
Equipped creature gets +1/+0 and has first strike.
Equip {3}

When Conscious Taboo enters, look at target opponent's hand. You may exile a noncreature, nonland card from it. For as long as that card remains exiled, its owner may play it. A spell cast this way costs {2} more to cast.

Create three 1/1 white Soldier creature tokens. Scry 3.

Whenever another creature you control enters, you gain 1 life.

Create a 1/1 white Soldier creature token with vigilance.
At the beginning of combat on your turn, you may pay {2}{W}. If you do, creatures you control get +1/+1 until end of turn.

Lifelink
Experience (Whenever this creature attacks, if it has fewer than three +1/+1 counters on it, put a +1/+1 counter on it.)

Machinate — {T}, Tap another untapped artifact you control: Exile target artifact or creature, then return that card to the battlefield tapped under its owner's control.

Advance {2}{W} (Cast this for {2}{W} to advance it as it enters. {2}{W}: Advance this as a sorcery.)
Whenever Construct Engine advances, create a 1/1 colorless Construct artifact creature token.

Constructed Jay is all colors.
Constructed Jay gets +1/+0 and has flying as long as you control three or more Satrapies.

At the beginning of your end step, return target creature card with mana value X or less from your graveyard to the battlefield with a finality counter on it, where X is the greatest number of creatures you control that share a creature type.

Scry 2, then draw two cards. You gain 2 life.
Monument {2}{W}{U} (You may cast this transformed from your graveyard for its monument cost. Exile it if it would leave the battlefield or not resolve.)

Enchant creature
Enchanted creature gets +1/+3.
{W}: Return Conviction to its owner's hand.

Level experience (Whenever this creature attacks, if it has fewer than three level counters on it, put a level counter on it.)
When Copperhide Calf has three or more level counters on it, remove them all and transform it. [2/2]
[level 1-3] Prevent the first 1 damage that would be dealt to Copperhide Calf each turn. [3/3]

Exile target creature with power 4 or greater.
Create a Treasure token. (It's an artifact with “{T}, Sacrifice this permanent: Add one mana of any color.”)

When Coralight Champion enters, create a white Aura enchantment token named Hila's Favor attached to target creature. The token has enchant creature and “Enchanted creature has double strike as long as there's another Aura attached to it. Otherwise, it has first strike.”

{3}{W}: Tap target creature. Activate only during your turn.