msem-instigator

You may play cards exiled with Azamir planeswalkers.
[+2]: Search each player's library for a card and exile it. Shuffle each library searched this way.
[–3]: Each opponent chooses a permanent they control for each permanent type, then exiles those permanents.
[–8]: Exile all cards your opponents own from outside the game. Until end of turn, you may cast spells without paying their mana costs and you may play cards exiled with Azamir planeswalkers.

Whenever Babbling Experiment or another creature you control enters, target player mills two cards.

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)

Mark (Whenever this creature attacks, mark target creature until end of turn.)
Whenever Backalley Silencer deals combat damage to a player, destroy target marked creature.

Non-Actor creatures can't block this turn.

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

{T}, Pay 1 life: Add {R} or {W}.
{1}, {T}, Sacrifice Backstage Rooms: Investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

When Backstage Tinkers enters, you may return an artifact card from your graveyard to your hand.

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

[+1]: Exile up to two target cards from graveyards. You gain 3 life.
[–2]: Exile target artifact, enchantment, or nonbasic land.
[–7]: You get an emblem with “At the beginning of your upkeep, exile target noncreature permanent.”

Flying
Sacrifice six Swamps: Return Berbarus Unsealed from your graveyard to the battlefield with an indestructible counter on it. You draw six cards and you lose 6 life.

When Bessie's Brood enters, it fights target creature. (If there are no other creatures, it eats itself.)

Trample
Bessie's Crusher has haste as long as you control another Wurm.

[+2]: Create a 3/3 red Wurm creature token.
[–2]: Up to three target creatures each get +2/+2 until end of turn. Bessie deals 2 damage to each of up to three target creatures.
[–9]: You get an emblem with “Creatures you control have base power and toughness 7/7 and have indestructible.”

Menace
When Bit Player dies, it deals 1 damage to each opponent.

{4}{R}: Blind Tunneler gets +3/+0 until end of turn.

Whenever Blood Artist or another creature dies, target player loses 1 life and you gain 1 life.

Draw a card for each creature that died this turn.

As long as you've gained life this turn, Bloodied Outcast gets +1/+0 and has lifelink.
As long as an opponent has lost life this turn, Bloodied Outcast gets +0/+1 and has deathtouch.

Bloodline Zealot gets +2/+0 and has menace as long as you've sacrificed a permanent this turn.

Mark (Whenever this creature attacks, mark target creature until end of turn.)
Bounty Crusher has trample as long as it's being blocked by a marked creature.

As Brave the Issbarrens enters, choose a color.
White creatures you control have protection from the chosen color. (This permanent can't be targeted, dealt damage, enchanted, or equipped by anything with that color.)

Enchant creature
Enchanted creature gets +2/+2 as long as it's an Actor. Otherwise, it gets -2/-2.

Flying, trample
Whenever Bretala of Redsky attacks, it gains double strike until end of turn unless defending player sacrifices a creature.

Tap up to four target nonland permanents. Nonland permanents your opponents control don't untap during their controller's next untap step.