msem-instigator

If a source you control would deal exactly 1 damage to a permanent or player, it deals 3 damage instead.

Whenever one or more creatures you control attack, create a 1/1 white Human Samurai creature token.

Whenever a creature you control enters, create an Idol token. (It's an artifact with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)
{2}, Sacrifice an Idol: Creatures you control get +1/+1 until end of turn.

Enchant creature
Enchanted creature and other creatures you control that share a creature type with it get +1/+1 and have vigilance.

Generative Edge enters tapped.
{T}: Add {G} or {U}.
{G}{U}, {T}, Sacrifice Generative Edge: Conjure a card named Data-Point into your hand. (It's a sorcery that costs {2} with “Draw a card.”)

When Generous Hermit dies, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Once each turn, you may cast a creature spell with mana value less than or equal to the number of names noted for Genetic Breakthrough without paying its mana cost.
{G}, Sacrifice a nontoken creature with a name not noted for Genetic Breakthrough and note its name: Draw cards equal to the sacrificed creature's power, then discard two cards.

When Genome Mapper enters, create a Function token with “Create an X/X green Mutant creature token, where X is this spell's mana value.” (It's an enchantment. As you cast an instant or sorcery spell, sacrifice any number of Functions to add their effects to that spell.)

Reach
Prismatic — Whenever you cast a multicolored spell, you gain 2 life.

Mark (Whenever this creature attacks, mark target creature until end of turn.)
Whenever Gentleman Thief deals combat damage to a player, gain control of target marked creature.

Whenever Gentry Infiltrator deals combat damage to a player, you may search that player's library for a creature card and exile it. If you do, that player shuffles.
{2}{U}{U}: Gentry Infiltrator becomes a copy of a creature card exiled with it until end of turn.

Flying, haste
Whenever one or more other nontoken Pirates and/or Rogues you control attack, create a 1/1 red Pirate creature token.

When Gharsha, Monstrous Quarry enters, each opponent creates a 1/1 green Elf creature token.
Whenever a creature you control becomes blocked, you may pay {1}. If you do, put a +1/+1 counter on that creature.

Ghastly Castle enters tapped unless another player controls a land that could produce {U} or {B}.
{T}: Add {U} or {B}.

When Ghastly Ferry enters, create a 1/1 white Spirit creature token with flying.
Ghastly Ferry can't be blocked except by Spirits.
Crew 1 (Tap any number of creatures you control with total power 1 or greater: This Ship Vehicle becomes an artifact creature until end of turn.)

Trample
When Ghastly Progenitor enters, each opponent reveals their hand. Choose two nonland cards revealed this way. Their owners discard those cards.

Deathtouch
When Ghastly Scorpion dies, you draw a card and you lose 1 life.

Creatures can't attack you or a planeswalker you control unless their controller pays {2} for each of those creatures.
Creatures can't block Ghastly Scraper unless their controller pays {2} for each of those creatures.

Flash

Flying
When Ghastly Spirit enters, mill four cards, then return a nonland card from your graveyard to your hand.

Creatures you control have deathtouch as long as they're attacking.
[+1]: Target creature you control must be blocked this turn if able.
[–2]: Create two 1/1 white Human creature tokens.
[–X]: Destroy target artifact or enchantment with mana value X and all other permanents with the same name as that permanent.

{T}: Draw a card, then discard a card.
Sacrifice Ghislain, Cryptbreaker: You may cast target creature, instant or sorcery card from your graveyard this turn. If that spell would be put into your graveyard, exile it instead. Activate only during your turn.

{2}, {T}: Prevent all combat damage that would be dealt to and dealt by target creature this turn.

{T}: Add {C}.
{T}, Sacrifice Ghost Quarter: Destroy target land. Its controller may search their library for a basic land card, put it onto the battlefield, then shuffle.