msem-instigator

Choose a creature. When it dies this turn, distribute two +1/+1 counters among any number of creatures you control.

Haste
When Doomed Alchemist dies, create two Treasure tokens. (They're artifacts with “{T}, Sacrifice this artifact: Add one mana of any color.”)

Enchant creature
Embody (Enchanted creature is a copy of this card except for its types.)
Whenever Fate of the Weary becomes tapped, create a 0/1 black Spirit creature token with flying.

Flying
Warden of Harshapal Tower's power and toughness are each equal to the number of creatures you control.

When Bauble Collector enters, you may return another permanent you control to its owner's hand.

Infiltrate (Whenever one or more attacking creatures you control aren't blocked, this creature gets +1/+1 until end of turn.)
When Exile's Vanguard enters, tap target creature. That creature doesn't untap during its controller's next untap step.

Equipped creature gets +1/+1.
Equip {1}

When this creature enters, put two -1/-1 counters on a creature you control.
When you put one or more -1/-1 counters on one or more creatures, tap target creature an opponent controls and put a stun counter on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)

(Transform this if it's not attached to a creature. Pay {3}{R}{R} as a sorcery to unattach it.)
Enchant creature you control
Mount of the Order's rider gets +5/+4.
{2}{R}: Target creature can't block Mount of the Order's rider this turn.

Lifelink
When Vel enters, choose up to one other target nonland permanent. If you gained or lost life this turn, exile that permanent until Vel leaves the battlefield.

Apothecary's Gift deals 5 damage to target creature or planeswalker. You gain life equal to the excess damage dealt this way.

[+1]: Each player discards a card at random, then draws a card.
[–2]: Until end of turn, gain control of target nonland permanent and it gains haste. Untap it.
[–6]: You get an emblem with “Whenever a source you control deals damage to an opponent, gain control of target permanent that player controls.”

Creatures you control get +1/+0 and gain haste until end of turn.

Motivate 1 (When this creature enters, you may motivate target creature with less power than this by putting a +1/+1 counter on it.)
{2}{W}{W}: Exile Valtrian Cavalier, then return it to the battlefield under your control.

Other artifacts you control have ward {1}.
Overcast — Whenever you cast an artifact creature spell, if {C} was spent to cast it, it enters with an additional +1/+1 counter on it.

Flying
Whenever another creature you control enters, create an Idol token.
Whenever you put a +1/+1 counter on Ya'Ling, put a +1/+1 on each other creature you control. This ability triggers only once each turn.

Equipped creature has hexproof. (That creature can't be the target of spells or abilities your opponents control.)
Equip {0}

Stampede — Whenever Exuberant Hunter and a creature with greater power attack, draw a card.

This spell costs {1} less to cast for each legendary creature you control.
Search your library for a legendary creature card with mana value X or less, put that card onto the battlefield, then shuffle.

Vigilance
When Coralight Sentinel enters, create a white Aura enchantment token named Crab's Resolve attached to target creature. The token has enchant creature and “Enchanted creature gets +0/+2.”

Whenever you cast a spell during an opponent's turn, put a charge counter on Gift of the Sphinx.
At the beginning of your upkeep, draw a card for each charge counter on Gift of the Sphinx.

Slipstream (This creature can't be blocked as long as only creatures with slipstream are attacking.)
When Dancer of the Great Current enters, tap up to one target creature. If you control two or more other creatures that are Merfolk, Wizards, or Rogues, instead return that creature to its owner's hand and put a +1/+1 counter on Dancer of the Great Current.

Hexproof
At the beginning of your upkeep, put a card from your hand on top of your library. You may shuffle.
{1}: Look at the top three cards of your library, then put them back in any order.
{2}{U}: Draw a card.

{T}: Add {C}.
{2}, {T}, Sacrifice Arcor Diamond: Draw a card.

Flying
This spell can't be countered.
When Frostbreath Dragon enters, tap target creature. It doesn't untap during its controller's next untap step.
Whenever Frostbreath Dragon becomes the target of a spell or ability, counter it unless its controller pays {2} and discards a card.