msem-instigator

Flash
When Seabreen Nullmage enters, counter target activated or triggered ability. (A triggered ability uses the words “when,” “whenever,” or “at”. Mana abilities can't be targeted.)

Spirited (When this creature enters, you may activate one of its activated abilities without paying its cost.)
Dragonmaw Wurm enters with X +1/+1 counters on it.
{1}{G}, {T}: Target creature you control fights another target creature.

This spell costs {2} less to cast if you cast it during your main phase.
Tap up to two target creatures. Put a stun counter on each of those creatures.

Unreflected Cultist can't be blocked by Reflections.

{T}: Add {C}.
{T}, Sacrifice a Clue: Draw a card.

Whenever equipped creature deals damage to a creature, that creature gets -2/-2 until end of turn.
Equip {2}

{T}: Add {G} or one mana of any color among cards in your graveyard.

When Three Seas Squire enters, target creature or Vehicle gets +2/+1 until end of turn.

Mark (Whenever this creature attacks, mark target creature until end of turn.)
Whenever a marked creature you don't control blocks, Cadalon Chemist deals 1 damage to that creature.

Whenever one or more other creatures you control enter, you gain 1 life. If at least one of those creatures was a Cleric, you gain 2 life instead.
As long as you have at least 8 life more than your starting life total, other Clerics you control get +1/+1.

Whenever a creature you control deals combat damage to an opponent or planeswalker, put a technology counter on Reclamation Project.
Remove X technology counters from Reclamation Project: You may cast target artifact or creature card with mana value X from your graveyard this turn. That creature enters as an artifact in addition to its other types. X can't be 0.

Look at the top four cards of your library. Put one of those cards into your hand and the rest into your graveyard.
Flashback {2}{B}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Return up to one target creature to its owner's hand. Then if this spell was foretold, you may destroy all creatures.
Foretell {1}{W}{W}{U} (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.)

Reveal up to four cards you own from outside the game with the same name, then shuffle them into your main library.
Draw a card.

Search your library for a Desert card or a land card with a basic land type and put it onto the battlefield tapped, then shuffle.

Until end of turn, creatures and artifacts you control gain “{T}: Tap target permanent.”

Cosmic Catastrophe deals 6 damage to target creature or planeswalker. If you control a creature with power greater than its base power, Cosmic Catastrophe deals 3 damage to each opponent.

When Barhopping in Minei enters, draw up to four cards, then put twice that many drink counters on Barhopping in Minei.
Your maximum hand size is reduced by the number of drink counters on Barhopping in Minei.

{2}, Sacrifice Walking Platform: Create a 1/1 colorless Thopter artifact creature token with flying.

Exile target artifact or enchantment. Its controller creates a Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)

Shuffle the cards from your hand into your library, then draw that many cards.
Draw a card.

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

Lifelink
When Telarine Runecarver enters, create a white Aura enchantment token named Relic's Gift attached to target creature. The token has enchant creature and “Enchanted creature gets +1/+1.”

[+1]: Boxue deals 1 damage to each opponent. You may draw a card, then discard a card.
[–1]: Create a Treasure token.
[–5]: Copy the next spell you cast this turn. You may choose new targets for the copy. (A copied permanent spell becomes a token.)