msem-instigator

[+1]: Draw a card unless an opponent discards a card.
[–3]: Gain control of target creature until the end of your next turn.
[–6]: Choose up to four cards in graveyards. You may play those cards without paying their mana costs.

S-19 Long Jacket has first strike as long as it's attacking.
S-19 Long Jacket has lifelink as long as it's blocking.

Until end of turn, target creature gets +2/+2, then an additional +2/+2 for each card and token merged with it.

Flying, haste
You may reveal each card you draw as you draw it. Whenever you reveal a creature card with mana value 1 or less this way, create a token that's a copy of it. That copy gains haste until end of turn.

Until end of turn, target creature gets +2/+2 and gains “Whenever this creature attacks, you may post a bounty on target creature.” (Put a bounty counter on that creature. It has “When it dies, each opponent draws a card” as long as it has a bounty counter on it.)

When Augmented Alchemist enters or dies, create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)

As an additional cost to cast this spell, sacrifice a creature.
Look at the top X cards of your library, where X is the sacrificed creature's power. Put one of those cards into your hand and the rest into your graveyard.

Flying
Harrier's Falcon can't attack or block alone.

{1}, {T}, Exile a land card from your graveyard: Add two mana in any combination of colors.
{B}{G}, {T}, Discard a card: Nourish 2. (To nourish 2, either put two +1/+1 counters on this creature or create two 1/1 white Citizen creature tokens.)

Whenever Heroic Exemplar attacks, if its power is greater than its base power, other creatures you control get +1/+1 until end of turn.

When All-Blossom Memorial enters, scry 1.
Prismatic — Whenever you cast a multicolored spell, you gain 1 life.
{T}: Add one mana of any color.

{1}, {T}, Sacrifice Looking Glass: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.
Kindle 1—{1} ({1}, Exile this card from your graveyard: Create a 1/1 colorless Elemental creature token. Kindle only as a sorcery.)

This spell costs {1} less to cast and can't be countered if it targets a cursed opponent.
Target opponent mills eight cards. Exile up to two nonland cards milled this way. Until the end of your next turn, you may cast those cards and mana of any type can be spent to cast those spells.

Target player discards a card and gets a poison counter.
Coalesce {4}{B}{B} (You may cast this from your graveyard for {4}{B}{B}. If you do, it enters as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)

Archive 5 (As this enters, shuffle the top five cards of your main library into a new face up library. Sacrifice this after the archived library is empty.)
You may play lands from the archived library.

When Meletis Oracle enters, scry 1, then draw a card.

Prowess, haste
Whenever you cast an instant or sorcery spell, you may shuffle the cards in your hand into your library, then draw that many cards.

Flying
Civilized — Whenever Edifice Overseer attacks, if you control an artifact, a creature, and an enchantment, other attacking creatures you control gain flying until end of turn.

Whenever Playful Surveyor attacks, reveal the top card of your library. If that card shares a color with a permanent you control, you gain 2 life.

When Auramancer enters, you may return target enchantment card from your graveyard to your hand.

Choose one —
• Shredding Blizzard deals 5 damage to target creature.
• Up to three target creatures can't block this turn.

You may look at the top card of your library.
{T}: You may play the top card of your library.

Exile two target cards from your graveyard. If they share a card type, draw a card. (Then exile this card. You may cast the creature later from exile.)

{1}{G}, Discard a card: Target land you control becomes a 3/3 Elemental creature. It's still a land. Exile the top card of your library face down.
Whenever a land creature you control deals combat damage to a player, put a card exiled with Children of Gos into your hand.

Beachhead Partisan has first strike as long as it's attacking.
When Beachhead Partisan enters, it deals X damage to any target, where X is the number of tapped creatures you control.