msem-instigator

This spell costs {2} less to cast for each Curse you control.
Flying, vigilance, haste

Target creature gets -4/-0 until end of turn.
Crystallize. (Put a +1/+1 counter on a creature you control or create a Treasure.)

Enchant creature
When Kalku Initiation enters, you lose 3 life and discard a card.
Enchanted creature gets +3/+2, has ward {2}, and has “Whenever this creature deals damage to a player, draw two cards.”

Flying
{2}{U}: Switch target creature's power and toughness until end of turn.

Target creature gains indestructible until end of turn. Scry 1. (To scry 1, look at the top card of your library. You may put that card on the bottom of your library.)
Fabled {3}{W} (Then if you cast this for its fabled cost, put it onto the battlefield transformed attached to that creature.)

{T}, Pay 1 life: Add {U} or {R}.
{1}, {T}, Sacrifice Heist Headquarters: Investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Fury Swipes deals 2 damage divided as you choose among one or two targets. Scry 2.

[+1]: Gain control of up to one target noncreature permanent you don't control until end of turn. Untap it.
[0]: Target player gains control of target permanent you control.
[–7]: You get an emblem with “Whenever you target one or more permanents, gain control of those permanents.”

Lifelink

Rhapsody {3}{R}{R} (Pay {3}{R}{R} to cast this as a 4/4, or as a sorcery to make it become a 4/4.)
Whenever Vindictive Guardian or another creature you control enters, if that creature's power is 4 or greater, create a Treasure token.

Exile target creature you control, then return it to the battlefield under its owner's control.
Flashback {2}{W} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Each creature you control with power 4 or greater can't be blocked by creature tokens.

Flying
Sacrifice Crystalcatcher: Counter target creature spell unless its controller pays {1}.

Trample
When Nanowrought Progenitor enters, draw a card for each creature you control with two or more card types.

Menace
Whenever another creature dies, put a +1/+1 counter on Veilborn Stalker.

Whenever you cast a noncreature spell, Sara, Entelan Elementalist gets +X/+0 until end of turn, where X is Sara's power. It deals 1 damage to each creature you don't control.

Concord — Whenever Chitinborn Sentry attacks, if there are four or more card types among permanents you control, prevent all damage that would be dealt to target attacking creature this turn.

First strike
Other creatures you control have protection from mana value 3 or greater.

Trample
When Depthlight Frontliner enters, you may salvage up to one instant card and up to one sorcery card. (Exile those cards from your graveyard until this creature leaves the battlefield. Whenever this creature deals combat damage to a player, put a card it salvaged into your hand.)

Opera House enters tapped.
When Opera House enters, add one mana of any color.
{T}, Sacrifice Opera House: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Reflections you control get +2/+2 until end of turn. Other creatures you control get +1/+1 until end of turn.

Prevent all combat damage that would be dealt this turn. Target player sacrifices an attacking creature.

Search your library for up to thirteen cards, exile them, then shuffle.
Draw three cards.

Whenever equipped creature blocks or becomes blocked by a creature, you may have equipped creature become a copy of that creature until end of turn.
Equip {1}

When Gruff Smith enters, you may destroy target artifact. If you do, that artifact's controller creates a colorless Equipment artifact token with “Equipped creature gets +1/+1” and equip {1}.
Recite {1}{R} (You may cast this creature from your graveyard for its recite cost. If you do, exile it when it enters or if it would leave the battlefield.)