msem-instigator

Experience (Whenever this creature attacks, if it has fewer than three +1/+1 counters on it, put a +1/+1 counter on it.)
Curious Cubs has first strike as long as its attacking.
When Curious Cubs has three or more +1/+1 counters on it, remove them all and transform it.

Elemental, Demon, and Spirit spells you cast cost {1} less to cast.
Whenever you cast a Elemental, Demon, or Spirit spell, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

I, II — Create a tapped Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)
Discovery — {2}, Sacrifice an artifact: Draw a card.

Whenever Current Shaper perseveres, it deals 1 damage to each opponent. (A creature perseveres when it survives damage.)

Enchant opponent
When Curse of Bleeding enters, enchanted player loses 2 life.
Enchanted player can't gain life.

Enchant opponent
Whenever a creature enters under enchanted player's control, that player loses 1 life and you gain 1 life.

Create a 2/2 colorless Spirit creature token.
When inscribed creature dies, create a 2/2 colorless Spirit creature token.
Inscribe {2}{B}{B} ({2}{B}{B}: Exile this card from your hand inscribed on a creature you control. Whenever that creature attacks, its controller may cast a copy of the inscribed card without paying its mana cost. Inscribe only as a sorcery.)

Enchant opponent
Creatures enchanted player control lose hexproof and indestructible and can't have or gain hexproof or indestructible.

Equipped creature gets +2/+1.
When equipped creature deals combat damage to an opponent, you may sacrifice Cursebreaker Hammer. If you do, destroy target artifact or enchantment that player controls.
Equip {2}

Counter target spell with mana value 3 or less.

When Customs Lookout enters, each player draws a card, then discards a card.
Whenever an opponent casts a spell with the same name as a card they own in exile or in their graveyard, you may scry 2.

Foretell {R} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)
If this spell is foretold, you may cast it as though it had flash.
Create two 1/1 red Pirate creature tokens.

Deathtouch
Cutthroat Deceiver enters with four -1/-1 counters on it.
{3}{B}, {T}: Move a -1/-1 counter from Cutthroat Deceiver onto another target creature.

Whenever Cutthroat Spy deals combat damage to a player, you may draw a card.

Put three -1/-1 counters on target attacking or blocking creature.

Creatures your opponents control get -2/-0 until end of turn. Scry 2.

CySec Infiltrator can't be blocked except by enchantment creatures.
Whenever CySec Infiltrator attacks, create a Function token with “Target player loses 2 life and you gain 2 life.” (It's an enchantment. As you cast an instant or sorcery spell, sacrifice any number of Functions to add their effects to that spell.)

Flash

{3}, {T}: Put a +1/+1 counter on target creature. This ability costs {3} less to activate if you've sacrificed a permanent this turn. Active only as a sorcery.

Enchant creature with mana value 4 or less
When Cyclic Dream enters, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.

[+2]: Until end of turn, you may spend mana as though it were mana of any type.
[0]: For each color, put a +1/+1 counter on a creature you control of that color.
[–7]: For each color, search your library for up to one creature card of that color. Put those cards onto the battlefield, then shuffle.

Creature spells you cast cost {2} less to cast.
Whenever another nontoken creature you control enters, it becomes a colorless Vehicle artifact with crew 1. (Tap any number of creatures you control with total power 1 or greater: That Vehicle becomes an artifact creature until end of turn.)

Reach (This creature can block creatures with flying.)
Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)

Adorned — Daelish Archer has first strike as long as it's equipped and/or enchanted.

Adorned — You may play an additional land on each of your turns as long as Daelish Horticulturist is equipped and/or enchanted.