msem-instigator

Enchant creature
Enchanted creature is a blue Shaman with base power and toughness 0/2, has “{2}, {T}: Scry 1,” and loses all other abilities.

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.)

Draw a card, then copy target activated or triggered ability you don't control. You may choose new targets for the copy.
Exile Confirm Hypothesis.

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.

An opponent separates all noncreature, nonland cards in your graveyard into two piles. Put one pile into your hand and exile the other. Exile Conflicting Records.

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

Target creature you control fights another target creature. (Each deals damage equal to its power to the other.)

Target creature you control gets +1/+0 until end of turn. It fights target creature you don't control.

As a spell you control is countered by a spell or ability an opponent controls while you control a Mountain, you may reveal Confront the Riddlemaster from your hand. When you do, cast it without paying its mana cost.
This spell can't be countered.
Confront the Riddlemaster deals 4 damage to any target.

Harness (You may tap a creature you control as you cast this spell. If you do, reduce this spell's mana cost by that creature's power.)
Return target nonland permanent to its owner's hand. If this spell was harnessed, draw a card.

Spend only mana of one color to cast this spell.

Abound. Then search your library for a creature, instant, or sorcery card, reveal it, put it into your hand, then shuffle. (To abound, you may cast a spell that costs less than this from your hand without paying its mana cost.)

When Conjured Shade dies, target creature you don't control gets -1/-1 until end of turn.

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.)

Destroy all noncreature, nonland permanents.

When Conniving Brigand enters, draw a card.

Deathtouch
Cadence (Whenever you cast a spell, if its mana value is greater than this creature's power, put a +1/+1 counter on this creature.)

Exile target creature you control, then return it to the battlefield under its owner's control. Create a token that's a copy of it. Those creatures gain haste until end of turn. Sacrifice the token at the beginning of the next end step.

Creatures you control get +1/+0 until end of turn. (Then exile this card. You may play the land later from exile.)

(Add a quest counter as this enters. Sacrifice after 3.)
Whenever you attack with one or more creatures with power 4 or greater, add a quest counter.
Until end of turn, target creature you control gains trample and “Whenever this creature deals combat damage to a player, put a +1/+1 counter on it.”
Put two +1/+1 counters on target creature you control. It fights up to one target creature you don't control.

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.

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.