msem-instigator

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.)
Artifacts and creatures your opponents control enter tapped.

Whenever a storied permanent you control enters, each opponent loses 1 life and you gain 1 life. (Enchantments and legendary permanents are storied.)
{2}{B}{B}, Sacrifice Sinister Heir: Return target storied card from your graveyard to the battlefield.

At the beginning of each upkeep, choose one or more —
• Untap target artifact.
• Untap target creature.
• Untap target land.

Whenever Skitterthorns blocks or becomes blocked, creatures you control gain deathtouch until end of turn.

Equipped creature gets +2/+2.
Whenever equipped creature deals combat damage to a player, you may put a permanent card with mana value 2 or less from your hand onto the battlefield.
Equip {2}

Whenever a creature dealt damage by Slave Child this turn dies, you may pay {B}. If you do, transform Slave Child.

Slay Them in the Aisles deals 2 damage to each non-Actor creature.

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.)
Slums Thug gets +1/+1 and has menace as long as you've gained life this turn.

Tap all lands target player controls and that player loses all unspent mana.

As Sorcerous Spyglass enters, look at an opponent's hand, then choose any card name.
Activated abilities of sources with the chosen name can't be activated unless they're mana abilities.

{1}, {T}: Exile target card from a graveyard. Scry 1.
{T}, Exile Soul Gate: Exile all graveyards.

Flash
Other Rogues you control get +1/+1.
Rogue spells you cast have flash.

Flying
Spirited (When this creature enters, you may activate one of its activated abilities without paying its cost.)
{5}: Each opponent sacrifices a nonland permanent.

Sacrifice any number of lands. Search your library for that many basic land cards, put them onto the battlefield, then shuffle.

Gain control of target nonland permanent. The player that controlled it creates a 3/3 blue Squid creature token.

{1}, {T}: Untap target creature.

Enchant creature or enchantment
Enchanted permanent doesn't untap during its controller's untap step.
Enchanted permanent can't have counters put on it.

Equipped creature gets +5/+5.
Whenever equipped creature becomes blocked, destroy all other creatures.
Equip {5}

Draw two cards. If you have no cards in hand and there are no cards in your graveyard, draw seven cards instead.

Flying
Whenever a player shuffles their library, Steamquiver Strix deals 2 damage to that player.

Whenever a permanent you control becomes tapped, Storm Servant gets +1/+1 until end of turn.

Whenever equipped creature attacks, it deals damage to defending player equal to the number of instant and sorcery cards in your graveyard.
Equip {2}

If you would lose the game, instead sacrifice a storied permanent. If you do and your life total is less than 1, it becomes 1.

Street Busker gets +2/+0 as long as you've gained life this turn.

When Street Stalker enters, target opponent loses 1 life for each creature you control named Street Stalker.