msem-instigator

When Benthic Alchemist enters, draw a card, then discard a card, then mill a card.
Whenever you cast an instant or sorcery spell, create a 1/1 colorless Elemental creature token. It gains haste until end of turn.

When Bio-Sequencer enters, conjure a card named Data-Point into your hand. (It's a sorcery that costs {2} with “Draw a card.”)
{1}, {T}, Sacrifice Bio-Sequencer: Add one mana of any color.

Exchange control of two target permanents that share a permanent type.
Lifecycle {3} ({3}, Discard this card: Create two tapped 1/1 colorless Elemental creature tokens.)

Target opponent reveals their hand. You choose an instant or sorcery card from it or a card from their graveyard. Exile that card.

When Blacksite Moderator enters, you may pay 2 life or sacrifice a permanent. If you do, draw a card.

Lifelink
{T}, Pay 4 life or sacrifice another permanent: Draw a card.

When Blackwall Ramparts enters, exile up to two target nonland permanents you don't control with total mana value 8 or less until Blackwall Ramparts leaves the battlefield.
Whenever you draw a card, you gain 1 life.

Double strike
Attain {3}{R} ({3}{R}: Transform this. Spend at least three colors of mana to activate this, and only as a sorcery.)

Haste
When Blighted Dullahan dies, you draw a card and you lose 1 life.

Breach (Whenever this deals combat damage to a player, you may have it become an Aura Curse until your next turn. Attach it to that player.)
At the beginning of your end step, each cursed opponent loses 2 life unless they discard a card.

When Bloodpact Collector enters, destroy target creature an opponent controls that was dealt damage this turn or has a -1/-1 counter on it.

Flying, prowess
When Bound Watcher enters, conjure a card named Data-Point into your hand. (It's a sorcery that costs {2} with “Draw a card.”)

Trample
{1}{G}: Brackish Kelpie gets +2/+2 until end of turn. Activate only once each turn.

When you cast this spell, copy it. You may choose new targets for the copy. (Copies keep functions.)
Draw a card.

First strike
Whenever you cast an instant or sorcery spell, if Branch Breaker dealt combat damage to a player this turn, you may sacrifice Branch Breaker. If you do, copy that spell. You may choose new targets for the copy.

Disgraced 2 (This enters with two -1/-1 counters. Whenever it deals combat damage to a player, remove all -1/-1 counters from it.)
When Branded Contractor dies, you may put its counters on target creature.

When Brawlhost Escapee dies, create a Function token with “Target creature you control fights target creature you don't control.” (It's an enchantment. As you cast an instant or sorcery spell, sacrifice any number of Functions to add their effects to that spell.)

Disgraced 1 (This enters with a -1/-1 counter. Whenever it deals combat damage to a player, remove all -1/-1 counters from it.)
When Bristling Baron dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control.

Target player mills four cards, then mills an additional four cards for each Curse attached to them.

Target creature gets +2/+0 and gains haste until end of turn.
Flashback {1}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Flying
When Byte Bug enters, conjure a card named Data-Point into your hand. (It's a sorcery that costs {2} with “Draw a card.”)

Flying
Whenever you gain life, each opponent loses 1 life.

When Cabinet of Curiosities enters, create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)
If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.

{T}, Pay 1 life: Add {R} or {G}.
{2}, {T}, Sacrifice Capital Towpath and another permanent: Draw a card. Activate only during your turn.

When Captured Mind dies, create a 3/3 white Construct enchantment creature token.