msem-instigator

When Azure Archaeologist enters the battlefield, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)
{2}, {T}, Sacrifice a Clue: Draw two cards, then discard a card.

Flying, trample
Prismatic — Whenever you cast a multicolored spell, put a +1/+1 counter on Azure Caterwauler.

First strike
Back-Alley Gnoll has lifelink as long as it's enchanted by a black Aura.
Back-Alley Gnoll gets +2/+0 as long as it's enchanted by a red Aura.

Haste
When Backdrop Artisan dies, audition for red. (Create a 1/1 Construct Actor creature token, a Warrior Role giving 3/2 and trample, or a Wizard Role giving 2/2 and prowess. Roles replace older ones.)

Non-Actor creatures can't block this turn.

When Backstage Broken enters the battlefield, create a 1/1 colorless Construct Actor creature token.
Whenever a token you control leaves the battlefield, you gain 1 life.

Lifelink
At the beginning of your end step, if you gained life this turn, put a +1/+1 counter on Backstage Manager.

At the beginning of your end step, create a 1/1 white Soldier creature token.

Basic Forests you control have “{G}, {T}: Untap target attacking creature and remove it from combat.”

As an additional cost to cast this spell, discard your hand.
Purge four times, then you gain 1 life for each card in exile. (Exile two cards that share a type from graveyards. If you do, draw a card.)

[+1]: Discard a card. If you do, up to one target player gains 5 life.
[–3]: Discard a card. You draw X cards and you lose X life, where X is that card's mana value.
[–7]: Exile your hand, then put all cards from your graveyard into your hand and all cards exiled this way into your graveyard.

(Transcend as a sorcery to gain that type and a +1/+1 counter.)
Flying
{1}{W}: Demigod — Return up to one target creature card with mana value 2 or less from your graveyard to the battlefield.
{3}{W}: God — Put a +1/+1 counter on each creature you control with the least power among creatures you control.

Prowess
Whenever Balefire Conjurer attacks, you may pay {1}{R}. If you do, exile the top card of your library. You may play that card until the end of your next turn.

Menace
As long as Balefire Harbinger is attacking, creatures in its pack can't be blocked unless defending player pays {1} and 1 life for each creature they control that's blocking one of those creatures. (Two or more creatures you control with equal power are in a pack.)

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 the battlefield, 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.

As an additional cost to cast this spell, sacrifice a creature.
All creatures get -X/-X until end of turn, where X is the sacrificed creature's power.

Exile target creature or planeswalker and all other creatures its controller controls with the same name as that permanent. Search its controller's graveyard, hand, and library for any number of nonland cards with the same name as that permanent and exile them. Then that player shuffles.

When Banished Prophet enters the battlefield, you may remove a counter from a permanent you control. If you do, put a +1/+1 counter on another target creature you control.

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

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

When Barbarian Hoarders enters the battlefield, you may attach target Equipment you control to it.

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

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

When Barhopping in Minei enters the battlefield, 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.