msem-instigator

Voracious 2 (As this enters, you may sacrifice up to two artifacts and/or creatures. This creature enters with that many +1/+1 counters on it.)
When Hunted Wolf enters, create a 2/2 black Soldier creature token.

Bloodprice {4}{B} (You may cast this card by sacrificing a creature and paying its bloodprice.)
At the beginning of your upkeep, if there are five or more creature cards in your graveyard, create a 2/2 black Demon creature token.

When Ninhasir's March enters, it deals 3 damage to any target.
{1}{R}{R}: Transform Ninhasir's March. Activate only if your fealty to Mountains is five or greater.

Each opponent plays with the top card of their library revealed.
During each of your turns, you may play one card from the top of an opponents' library, and you may spend mana as though it were mana of any color to cast that spell.

Equipped creature gets +1/+1 for each card in your hand.
Equip {3}

Whenever you cast your first noncreature spell each turn, you may cast a creature spell with lesser mana value from your hand without paying its mana cost.
Whenever you attack with three or more creatures, target instant or sorcery card in your graveyard gains flashback until end of turn. The flashback cost is equal to its mana cost.

{G}, {T}: Put a +1/+1 counter on Bloodleaf Tracker for each creature that entered this turn.

Arm target creature you control. It deals damage equal to its power to any target. (Create a colorless Equipment artifact token with “Equipped creature gets +1/+0” and equip {2}, then attach it to that creature.)

Slipstream (This creature can't be blocked as long as only creatures with slipstream are attacking.)
Sacrifice Bonetooth Darter: Counter target instant, planeswalker, or sorcery spell unless its controller pays {1}.

Choose one —
• Destroy target artifact.
• Add {R}{R}{R}.

When Spirit of Autumn enters, nourish X, where X is the number of creatures you control. (To nourish X, either put X +1/+1 counters on this creature or create X 1/1 white Citizen creature tokens.)

Siphon (Each -1/-1 counter you put on your creatures up to their remaining toughness while casting this pays for {1}.)
Bloodfall deals 8 damage divided as you choose among up to eight targets. If you spent exactly {R} for this spell's mana payment, it deals 8 damage to each of those targets instead.

Target creature gets -X/-X until end of turn, where X is the number of enchantments you control.

Target player mills five cards.
Draw a card.

Flying
Whenever you cast a spell from anywhere other than your hand, Brightwing Sphinx gains vigilance until end of turn.

Whenever Student of Winds attacks, upgrade target attacking creature. (Give it one of the listed counters it doesn't already have.)
• +1/+1
• Flying

Whenever a creature you control deals combat damage to a player, it cackles. (Put a menace counter on it. If it already has menace, it deals 1 damage to each opponent instead.)
{3}{B}: Each creature you control with menace gains lifelink until end of turn.

Each instant and sorcery card in your hand has cycling {2}. ({2}, Discard this card: Draw a card.)
At the beginning of your end step, if there are four or more instant and/or sorcery cards in your graveyard, you may pay {1}{U/R}. If you do, return an instant or sorcery card at random from your graveyard to your hand.

Whenever Valinov Collector or another artifact you control enters, Valinov Collector deals 2 damage to each opponent and you gain 2 life.

When Aminatou's Adherent enters, judge target creature you control. (Honor it by putting a +1/+1 counter on it or condemn it by sacrificing it to draw a card.)
Whenever you condemn a creature, creatures you control gain menace until end of turn.

Defender
Your maximum hand size is thirteen.
{T}: If you have fewer than thirteen cards in hand, draw cards equal to the difference. Activate only as a sorcery.

Equipped creature gets +3/+1 and has haste.
Equip Soldier or Warrior {1}
Equip {4}

Enchant opponent
Creatures enchanted player controls get -1/-0.

When Seeker of Communions enters, choose target player. If that player is poisoned, draw a card. Otherwise, that player gets a poison counter.