msem-instigator

Target creature gets +1/+0 and can't be blocked this turn.
Showcase {2}{U} (Then if you cast this for its showcase cost, create a 1/1 red Bard creature token that can't block and exile this. Whenever it attacks, you may cast a free copy of this.)

Primordial Slime can't be blocked by creatures with power 2 or less.
When Primordial Slime dies, you gain 5 life.
Foreshadow {5}{G}{G} (You may cast this spell for its foreshadow cost. If you do, also trigger its “dies” abilities when it enters.)

Legacy (You may play this side of this card only from your graveyard. Exile it if it would leave the battlefield or not resolve.)
Permanents you control have lifelink and “{T}: Add one mana of any color.”

Diligent Believer gets +1/+1 for each +1/+1 counter on other creatures you control.

When Evershedder dies, you may put it on the bottom of its owner's library.
Morph {2}{B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Whenever a player casts a spell, that player reveals cards from the top of their library until they reveal two land cards, then puts all cards revealed this way into their graveyard.

When Wu, the Shackled enters, you may have an opponent gain control of it. If you do, draw two cards.
At the beginning of your upkeep, if you don't own Wu, it fights another target creature you control and its owner draws a card.

Mark (Whenever this creature attacks, mark target creature until end of turn.)
Whenever a marked creature dies, target player discards a card.

You may have Imaginative Dreamer enter as a copy of any creature on the battlefield. When it does, it stops being a copy.

Kaur, End of Lies costs {X} less to cast, where X is the greatest mana value among permanents your opponents control.
[+2]: Reveal the top card of your library. If it's a permanent card, put it onto the battlefield.
[–4]: Exile target noncreature permanent, then reveal the top four cards of your library. You may put a permanent card from among them onto the battlefield. Put the rest into your graveyard.
[–12]: Search your library for up to X permanent cards, where X is the number of permanents you control, put them onto the battlefield, then shuffle.

When Amira, Grand Inventor enters, create a 1/1 colorless Construct Artificer artifact creature token. If you control six or more artifacts, create a 6/6 colorless Golem artifact creature token instead.
Artifact tokens you control have all activated abilities of other artifact tokens you control.

Once each turn, when you activate an ability of a permanent you control that isn't a mana ability, you may exile that permanent. If you do, return that card to the battlefield under its owner's control at the beginning of the next end step.

Flying, lifelink

Discard your hand. Draw cards equal to the number of creatures that died this turn.

Gain control of target creature until end of turn and untap it. Until end of turn, it gains haste and “Whenever this creature attacks, it deals 2 damage to itself.”

Flying
Whenever Rubble Scavenger deals combat damage to a player, you may return target artifact card with mana value 4 or less from your graveyard to the battlefield.

Menace
Swampcycling {1}, forestcycling {1} ({1}, Discard this card: Search your libary for a Swamp or Forest card, reveal it, put it into your hand, then shuffle.)

As long as you control exactly one creature, no more than one creature can attack or block each combat.

Return up to two target creature cards from your graveyard to your hand.

Return up to one target permanent or Revelation card from your graveyard to your hand.
Coalesce {5}{B}{G} (You may cast this from your graveyard for {5}{B}{G}. If you do, it enters as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)

First strike
{1}{R}, Discard a card: East Ward Forgetender gets +2/+0 until end of turn.

Beckon Ox {1}{W} ({1}{W}: This enchantment permanently becomes an Ox creature in addition to its other types.)
Vigilance
Whenever a creature or another enchantment you control enters, you gain 1 life.

Flash
When Aethermancer's Familiar enters, at the beginning of the next end step, you may aetherize target creature you control. (To aetherize, create a token that's a copy of it, then exile that token.)

Whenever you gain life, amass Zombies 1. (Put a +1/+1 counter on an Army you control. It's also a Zombie. If you don't control one, create a 0/0 black Zombie Army creature token first.)
If you would gain life except for the first time each turn, instead each opponent loses 1 life. (If multiple sources would cause you to gain life at the same time, choose one to be first.)

When Sealed Riftway enters, exile up to one target card from a graveyard.
{2}, {T}, Sacrifice Sealed Riftway: Exile target player's graveyard. Draw a card.