msem-instigator

This spell costs {U} less to cast if you dealt combat damage to a player this turn with a Rogue.
Flying
When Balloon Voyager enters, draw a card.

At the beginning of combat on your turn, if there are five or more creature types among creatures you control, creatures you control get +2/+0 and gain menace until end of turn.

Whenever equipped creature attacks, it gains deathtouch until end of turn.
Sacrifice Bandit's Dagger: Target player dealt damage by equipped creature this turn reveals their hand. You choose a nonland card from it. That player discards that card.
Equip {2}

Engorge (As this enters, mill three cards, then exile a card from among the milled cards.)
When Bane of Sanity enters, if it engorged a creature card, target player discards two cards.

Exile up to three target cards from graveyards. (Then exile this card. You may cast the creature later from exile.)

When Banishing Initiate enters, you may exile target nonland permanent you don't control until Banishing Initiate leaves the battlefield.
At the beginning of your end step, sacrifice Banishing Initiate if a card exiled with it has mana value 3 or greater.

Lifelink
{1}, Discard Bant Shardseeker: Search your library for a basic Island or Forest card, reveal it, put it into your hand, then shuffle.

Golden age (If you cast an instant or sorcery spell, activated a nonmana ability, and attacked this turn, enter a renaissance for this game.)
Baptism by Fire deals 3 damage to target creature or planeswalker. If you're in a renaissance, Baptism by Fire deals 6 damage to that permanent instead.

Vigilance
{1}{W}: Barbarian Axe Flinger gains double strike until end of turn.

When Barbarian Intimidator enters, target creature can't block this turn.
When Barbarian Intimidator enters, prevent all combat damage that would be dealt to target creature this turn.

Other Warriors you control have first strike.
Other Barbarians you control get +1/+0.

Battalion — Whenever Barbaric Ambusher and at least two other creatures attack, you may tap target creature.

Until end of turn, target creature gets +1/+1 for each Equipment attached to it and gains flying and first strike.

Deathtouch
Whenever a creature dealt damage by Barbed Beast this turn dies, transform Barbed Beast.

Vigilance, deathtouch
Whenever a creature dealt damage by Barbed Bruiser this turn dies, draw a card.

Barbed Reef enters tapped. When it does, it explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on this, then you may put that card into your graveyard.)
{T}: Add {B}.
{4}{B}: Barbed Reef becomes a Jellyfish creature. (This effect lasts indefinitely.)

Whenever Barker Duelist becomes blocked, defending player loses 1 life.
Unveil {3}{B}{R} ({3}{B}{R}: Transform this. Unveil only as a sorcery.)

When Barking Irons enters, if it's not a token, create a token that's a copy of it.
Equipped creature gets +2/+0.
Equip {2}

Barren Vista enters tapped.
{T}: Add {U} or {B}.
{1}, {T}: Add one mana of any color.

{1}{U}: Target creature you control can't be blocked this turn by creatures with less power.
{1}{U}: Target creature you control can't be blocked this turn by creatures with greater power.

Vigilance
Whenever Bartimus attacks, another target attacking creature gets +1/+1 until end of turn. If that creature is a Soldier, put a +1/+1 counter on it instead.

When Basalt Ritualist enters, you may sacrifice a land or exile a land card from your graveyard. When you do, exile target creature, instant, or sorcery card from your graveyard. Until the end of your next turn, you may play that card. If that spell would be put into a graveyard, exile it instead.

Discard your hand, then draw three cards. Bask in Fire deals 2 damage to each creature.

Lifelink
When Bastion Chaplain enters, create two Function tokens with “Lifelink.” (They're enchantments. As you cast an instant or sorcery spell, sacrifice any number of Functions to add their effects to that spell.)

Create two 1/1 white Avatar enchantment creature tokens with prowess.
Conjure a card named Data-Point into your hand. (It's a sorcery that costs {2} with “Draw a card.”)