msem-instigator

Draw a card. If this is the third spell you've cast this turn, create a 2/2 blue Drake creature token with flying. If this is the sixth spell you've cast this turn, exile it, then return up to three target instant and/or sorcery cards from your graveyard to your hand and untap up to six lands.

Flash
Harmony — Another target creature gets +1/+0 and gains indestructible until end of turn.
When Siamang Tale-Singer enters the battlefield, harmonize. (Trigger up to one harmony of a permanent you control.)

When Sift Through False Leads enters the battlefield, exile the top five cards of your library, then investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)
{2}, Sacrifice a Clue: Put a card exiled with Sift Through False Leads into your hand.

When Sights Beyond enters the battlefield, scry 3.
Concord — At the beginning of your upkeep, if there are four or more card types among permanents you control, draw a card.

Creature tokens you control get +1/+0.

When Silence Dissent enters the battlefield, each player exiles a card from their hand at random until Silence Dissent leaves the battlefield.
{1}{W}: Exile Silence Dissent. Return it to the battlefield under your control at the beginning of your next end step.

Return target creature to its owner's hand. If you controlled that creature, draw a card.

Return target creature card from your graveyard to your hand.
Compose (Then if you cast this from your hand, exile it and create a Saga token with “III—You may cast a copy of this card from exile without paying its mana cost.”)

Target player reveals a number of cards from their hand equal to the number of creature cards in your graveyard. You choose one of them. That player discards that card.

Target creature gains trample and haste until end of turn. Harmonize. (Trigger up to one harmony of a permanent you control.)

Mill a card. Target creature gets -X/-X until end of turn, where X is the number of cards put into your graveyard from anywhere this turn.

Whenever an opponent is dealt damage by one or more sources you control for the second time each turn, draw a card.

Whenever Skitterthorns blocks or becomes blocked, creatures you control gain deathtouch until end of turn.

Until end of turn, target creature you control gets +1/+1 and target creature an opponent controls gets -1/-1.

{3}{W}: Tap target creature with power 4 or greater.

Enchant creature
Enchanted creature gets +1/+1 and has flying.

Target creature blocks this turn if able. You may have it gain reach until end of turn.
Draw a card.

Look at the top two cards of your library. Put one of them into your hand and the other on the bottom of your library.

First strike
{2}{R}: Monstrosity 2. (If this creature isn't monstrous, put two +1/+1 counters on it and it becomes monstrous.)

Destroy target enchantment. If it's a Curse, you gain 3 life.

You draw a card and you lose 1 life.
When Small Luxuries is put into your graveyard from your hand or library, put it into your hand from your graveyard at the beginning of the next end step.

Goad up to one target creature. (Until your next turn, that creature attacks each combat if able and attacks a player other than you if able.)
Draw a card.

Target creature can't block this turn. Smokescreen deals 2 damage to that creature's controller.

Equipped creature gets +0/+2 and has menace.
Equip {1}

Target creature gains deathtouch and poisonous 1 until end of turn. (Whenever that creature deals combat damage to a player, that player gets a poison counter.)
Inscribe {1}{G} ({1}{G}: Exile this card from your hand inscribed on a creature you control. Whenever that creature attacks, its controller may cast a copy of the inscribed card without paying its mana cost. Inscribe only as a sorcery.)