msem-instigator

{T}, Discard a card: Draw a card.
{2}{R}, {T}: Copy target instant or sorcery spell you control. You may choose new targets for the copy. Activate only if you have four or more instant and/or sorcery cards in your graveyard.

Lifelink
At the beginning of your upkeep, Osgaerith Desecrator deals 1 damage to up to one target creature.

Improve {G} ({G}: Put a +1/+1 counter on this creature. This costs {1} more to activate for each +1/+1 counter on it. Improve only as a sorcery.)
When Pack Huntress enters, create a 2/2 green Wolf creature token.

Once during each of your turns, you may cast a legendary creature or planeswalker spell from your graveyard.
Sacrifice Pallid Herald: Exile up to three target cards from graveyards.

At the beginning of your postcombat main phases, add an amount of {R} equal to the number of creatures you controlled that dealt combat damage to a player or planeswalker this turn.

Look at the top four cards of your library. Put two of them into your hand and the rest on the bottom of your library in a random order. Create a tapped Treasure token.

Deathtouch
When Pestilent Scavenger enters, you may mill three cards.

Deathtouch, lifelink
Improve {1}{W/B} ({1}{W/B}: Put a +1/+1 counter on this creature. This costs {1} more to activate for each +1/+1 counter on it. Improve only as a sorcery.)
{4}: Target creature gains deathtouch and lifelink until end of turn. Activate only during a player's first main phase.

{T}: Add {C}.
{T}, Pay 1 life: Add one mana of any color.

Flying
Whenever Pledged Griffin attacks, another target attacking creature gains flying until end of turn.

Put two +1/+1 counters on target creature you control. When you do, it deals damage equal to its power to up to one target creature with flying.

When Poisoned Shiv enters, destroy target creature or planeswalker.
Equipped creature gets +2/+0 and has deathtouch.
Equip {2}

{2}{U}: Target creature can't be blocked this turn.

When Practiced Sorcerer enters, return target noncreature, nonland card from your graveyard to your hand.

When Prophetic Prism enters, draw a card.
{1}, {T}: Add one mana of any color.

Pulverize the Intruders deals 4 damage to any target. Create a 4/4 red Giant creature token. It gains haste until end of turn if you control a legendary creature.

Prowess
Landfall — Whenever a land you control enters, create a 1/1 green, blue, and red Elf Scout creature token with prowess.

When Radiant Rebuker enters, exile target nonland permanent an opponent controls until Radiant Rebuker leaves the battlefield.

Look at the top six cards of your library. Put up to one land card and up to two creature and/or planeswalker cards with total mana value 5 or less from among them onto the battlefield. Put the rest on the bottom of your library in a random order.

Flying
When Razorwing Champion enters, creatures you control get +1/+1 and gain vigilance until end of turn.

Scry 2, then draw a card.
If you control a legendary permanent, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Put target artifact, enchantment, or card in a graveyard on the bottom of its owner's library.

Choose two target creatures controlled by different players. Return those creatures to their owners' hands.

Menace
Regal Dragoon gets +1/+1 as long as you control a legendary creature.