msem-instigator

When Abyssal Nightcaster enters, each player exiles a card from their hand.
When Abyssal Nightcaster dies, you may play cards you don't own from exile this turn.

{B}, {T}, Discard a card: Search your library for a card, then shuffle and put that card on top. You lose 2 life.

Whenever equipped creature deals combat damage to a player, put a +1/+1 counter on it and draw a card.
Equip {1}

After a player chooses two or more modes while casting a spell, you may pick one of those modes. That mode is no longer chosen. (That player doesn't pick targets or pay costs related to that mode. If a mode is chosen multiple times, only one instance of that mode is lost.)

Double strike

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.)

Non-Human creatures you control get +1/+0.

As an additional cost to cast Acid Sewage, reappropriate or pay {3}. (To reappropriate, exile exactly two cards from your hand and/or graveyard.)
Destroy target creature.

Target instant or sorcery spell gains “This spell deals 4 damage to you.”

Lifelink
When Adept of Transfusions enters, create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)
Tokens you control have “{1}, {T}, Discard a card, Sacrifice this token: Draw a card.”

Choose one —
• Destroy target artifact.
• Destroy target enchantment.
• Tap target creature and put two stun counters on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)

Each spell you cast with flash or haste costs {1} less to cast.
Each creature you control with flash or haste gets +1/+0.

Advanced Powercell enters tapped.
{T}: Add one mana of any color.

Choose one —
• Create three X/X colorless Construct artifact creature tokens.
• Create X tokens that are copies of target artifact you control.

As an additional cost to cast this spell, discard a card.
Advent from Above deals 3 damage to any target. Exile the top two cards of your library. You may play those cards during any turn you attacked with an artifact creature.

Look at the top five cards of your library. You may reveal a creature card from among them and put it into your hand. Put the rest on the bottom of your library in a random order. If you didn't put a card into your hand this way, draw a card.

First strike
Whenever a player loses life, creatures you control get +1/+0 until end of turn.

Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
Heroic — Whenever you cast a spell that targets Aegis Hero, put a +1/+1 counter on Aegis Hero.

Equipped creature has vigilance.
Equipped creature gets +3/+3 as long as you control a Spirit.
Equip {1}

Rapport — Whenever Aelinn, Serpent's Voice and at least one other creature you control become tapped, reveal the top card of your library. You may cast that card. If you don't, put it into your graveyard and Aelinn, Serpent's Voice deals 2 damage to each opponent.

Flying, double strike

{T}, Discard a card: Draw a card from each of your libraries.
{1}{U}{R}, {T}, Discard your hand: Return each Study card from your graveyard to your hand.

Flying, first strike

Enchant creature
When Aerie Watch enters, draw a card.
Enchanted creature gets +1/+1 and has reach.

Spells you cast from anywhere other than your hand cost {1} less to cast.
Whenever an opponent casts a spell with the same name as a card they own in exile or in their graveyard, that player loses 1 life and you gain 1 life.