msem-instigator

{1}{B}, Sacrifice another creature: Put a +1/+1 counter on Voracious Ghoul.

Whenever another non-Zombie creature you control dies, create a tapped 2/2 black Zombie creature token.
{B}, Sacrifice a creature: Target creature gains deathtouch until end of turn.

Discard a card: Warpblade Warrior gets +1/+1 and gains menace until end of turn. Activate only once each turn.

Whenever Wasting Soul attacks or blocks, sacrifice a creature, then put two +1/+1 counters on Wasting Soul.

When Wilting Waif dies, each opponent discards a card at random and you scry 1. (To scry 1, look at the top card of your library. You may put that card on the bottom of your library.)

Inspired — Whenever Yenzu Disciple becomes untapped, each opponent loses 1 life and you gain 1 life.

When Academy Renegade enters, it deals damage to target creature you don't control equal to the number of Wizards you control.
Whenever Academy Renegade attacks, it deals damage to defending player equal to the number of Wizards you control.

Menace
Cadence (Whenever you cast a spell, if its mana value is greater than this creature's power, put a +1/+1 counter on this creature.)

You may exert Accursed Bear as it attacks. When you do, it gets +1/+0 and gains trample until end of turn. (An exerted creature won't untap during your next untap step.)

Sacrifice a creature: Until end of turn, Advocate of Foibles gets +2/+0 and becomes a Demon in addition to its other types.
{1}{B}{G}: Amass Soldiers 1. (Put a +1/+1 counter on an Army you control. It's also a Soldier. If you don't control one, create an 0/0 black Soldier Army creature token first.)

Menace, haste
Whenever Aiel's Fury attacks, scry 2, then reveal the top card of your library. Aiel's Fury gets +X/+0 until end of turn, where X is that card's mana value.

Haste
{R}: Akoum Rockhurler gets +1/+0 until end of turn.
Whenever Akoum Rockhurler attacks, you may sacrifice a land. If you do, put two +1/+1 counters on Akoum Rockhurler.

At the beginning of your upkeep, you may sacrifice a Goblin. If you do, Alenian Boom Squad deals 2 damage to any target.

Whenever Apprehensive ‘Slinger deals combat damage to a player or planeswalker, you may discard a card. If you do, draw a card.

Other creatures you control can't attack or block alone.

Whenever Arcane Metalcrafter or another Wizard you control attacks, create a 1/1 colorless Construct artifact creature token that's tapped and attacking.
Whenever a Construct you control dies, Arcane Metalcrafter deals 1 damage to each opponent.

Whenever Arena Challenger deals damage to a creature, upgrade it. (Give it one of the listed counters it doesn't already have.)
• +1/+1
• First strike
• Prowess

As long as Armed Vendor is enchanted or equipped, it gets +1/+0 and has menace.

Whenever you cast an Inscription spell, you may choose target creature you control. If you do, as that Inscription resolves, exile it inscribed onto that creature instead of putting it anywhere else.

Whenever Aspect of An'yama attacks, surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)
Spells you cast from your graveyard, activated abilities of cards in your graveyard, and reprise costs of spells you cast cost {1} less.

{1}, Sacrifice a creature or enchantment: Exile the top card of your library. You may play that card this turn.

Menace, haste

Haste
Whenever Banished Companion attacks, it deals 2 damage to you.

Trample
Whenever another Dwarf you control enters, create a colorless artifact token named Ale. It has “{T}, Sacrifice this artifact: Target creature gets +2/+0 until end of turn. Activate only as a sorcery.”

Haste
{2}{U}: Copy target instant or sorcery spell you control. You may choose new targets for the copy. Activate only if you attacked with a Pirate or Rogue this turn.