msem-instigator

Whenever a player casts a spell, put a time counter on Chronovore Clock. Then if there are ten or more time counters on it, remove all time counters from it and end the turn.

Flying
Vanishing 3 (This creature enters with three time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
If Chronowing Phoenix would die while it had no time counters on it, instead exile it, then return it to the battlefield.

Death knell — Add {G}. (As a creature you control dies, trigger one death knell of that creature or another permanent you control.)
{W}{B}{G}: Trigger a death knell of target permanent you control.

{2/R}{2/R}: Churning Rough-Roller gets +1/+1 and gains double strike until end of turn.

When Churning Sandwurms enters, remove all counters from target permanent. Put a +1/+1 counter on Churning Sandwurms for each counter removed this way.

When Churning Spellroot enters, create three 1/1 black Worm creature tokens.

Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)

[+2]: You may sacrifice a permanent or discard a card. If you do, draw a card.
[–X]: Return target creature card with mana value X or less from your graveyard to the battlefield.
[–8]: You get an emblem with “Whenever a permanent you control dies, return a permanent card with lesser mana value from your graveyard to the battlefield.”

Cinder Arrows deals 3 damage to target creature.

Equipped creature has haste.
Sacrifice Cinderblade: Equipped creature gains +2/+2 until end of turn.
Equip {1}

Flying, haste
Arise {4}{R}. This ability costs {1} less to activate for each instant and sorcery card in your graveyard. ({4}{R}, Exile this from your graveyard as a sorcery: Create a black token copy of it that's also a Zombie and can't block.)

Trample
Whenever a player casts a spell, Cinderhoof Minotaur deals 1 damage to that player.
Whenever Cinderhoof Minotaur attacks, add {R}. Until end of turn, you don't lose this mana as steps and phases end.

Each player discards their hand and sacrifices five lands. Cinders of an Old Era deals 5 damage to each creature and planeswalker.
At the beginning of each player's next first main phase, that player draws seven cards and adds five mana in any combination of colors.

Circling Predators deals X damage to each creature, where X is 2 plus the number of cards with a cycling ability in your graveyard.
Cycling {2} ({2}, Discard this card: Draw a card.)

Flying
Whenever Circumspect Flock perseveres, create a 1/1 white Bird creature token with flying. (A creature perseveres when it survives damage.)

{1}{R}: Circus Firebreather gets +1/+0 until end of turn.

Citadel Bagworm gets +0/+1 for each card in your graveyard.
{B}, Discard a card: Switch Citadel Bagworm's power and toughness until end of turn.

{3}{G}: Search your library and/or graveyard for an Aura card, reveal it, and put it into your hand. If you search your library this way, shuffle.
{1}{U}: Untap target creature.

As Citadel Gates enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {B}, {R}, or {G}.

{X}, {T}: Reveal the top card of your library. If its mana value is X or less, you may play it without paying its mana cost. Otherwise, put it into your hand. X can't be 0.

{T}: Add {C}.
{1}{C}{C}, {T}: Return target legendary creature to its owner's hand.

{T}: Add {C}.
{3}, {T}, Sacrifice City Gate: Put two +1/+1 counters on target creature you control that attacked this turn.

When Citywide Automation enters, create two 1/1 colorless Construct artifact creature tokens.
{2}{W}{W}, Sacrifice Citywide Automation: Creatures you control get +1/+1 until end of turn. Activate only as a sorcery.

Target creature attacks or blocks this turn if able.
Forebode. (Create a tapped colorless Omen artifact token with “{T}, Discard a card, Sacrifice this artifact: Draw a card.”)

Civilization's Cost deals damage to each player equal to the number of nonbasic lands that player controls.
Flashback {R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)