msem-instigator

You may reveal the second card you draw each turn as you draw it. When you do, create a 2/2 blue Avatar Wizard creature token with prowess if it's a creature card. If it's a land card, create a Treasure token. If it's a noncreature, nonland card, Steward of Second Sphere can't be blocked this turn.
{3}{W/U}{W/U}: Scry 2.

Dustchoked Outpost enters tapped.
When Dustchoked Outpost enters, create a 1/1 Scout creature token that's all colors. It gains haste until end of turn. Sacrifice it at the beginning of the next end step.
{T}: Add {R}.

Whenever you cast a creature spell, create an Idol token. (It's an artifact with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)
Whenever you sacrifice an Idol, draw a card.

Vigilance
{T}: Add {G}.

{T}, Sacrifice Merchant's District: Search your library for an Island or Mountain card and put it onto the battlefield tapped, then shuffle.

Wesgoth Cemetery enters tapped.
Whenever a nontoken creature dies, put a corpse counter on Wesgoth Cemetery.
{T}: Add {B} or {G}. If there are thirteen or more corpse counters on Wesgoth Cemetery, remove those counters, transform it, then untap it.
Wesgoth Cemetery can be your commander.

Whenever Dapper Ragamuffin attacks, it gets +2/+0 until end of turn if you control another attacking Pirate.

At the beginning of your first main phase, add an amount of {G} equal to Bloomhorn's power.

Prowess
When Rosebud Runner enters, exile the top card of your library. During your next turn, you may play that card from exile.

Melee (Whenever this creature attacks, it gets +1/+1 until end of turn for each opponent you attacked this combat.)
Whenever Tegan, the Sparrowhawk attacks, you may pay {R/W}. When you do, Tegan deals 1 damage to target creature if it's tapped. Otherwise, tap it.

Autumn Ward's power and toughness are each equal to the number of creature cards in your graveyard.
Unveil {2}{B}{G} ({2}{B}{G}: Transform this. Unveil only as a sorcery.)

Counter target spell.
Forebode. (Create a tapped colorless Omen artifact token with “{T}, Discard a card, Sacrifice this artifact: Draw a card.”)

When Posthumous Informant dies, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Golden Company Valiant can block any number of creatures.
At the beginning of combat on each opponent's turn, Golden Company Valiant gets +1/+1 until end of turn for each creature that player controls.

Shadow Courier can't be blocked.

Other Hounds you control get +1/+1.

Equipped creature has “{1}, {T}: This creature deals 1 damage to any target.”
Whenever equipped creature deals damage to a creature with power 5 or greater, sacrifice Sling of the Meek. If you do, destroy that creature.
Equip {3}

You may play Anemone Cluster from your graveyard as long as seven or more cards are in your graveyard.
Anemone Cluster enters tapped.
{T}: Add {G} or {U}.
Cycling {1}{G}{U} ({1}{G}{U}, Discard this card: Draw a card.)

Haste
When Gilded Gearhulk enters, you may destroy target noncreature, nonland permanent.

Flying
Whenever you cast a spell, Gilded Hawk gets +1/+1 until end of turn for each of that spell's colors.

Create an 8/8 blue Kraken creature token with hexproof.
Rerun (If you cast this from your hand, exile it as it resolves. Whenever a creature you control dies, you may cast this card from exile without paying its mana cost.)

Create a 1/1 blue Bird creature token with flying.
Inscribe {2}{U} ({2}{U}: 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.)

[+1]: Up to one other target permanent gains hexproof and indestructible until your next turn.
[–3]: Destroy target tapped permanent.
[–7]: You get an emblem with “If you would lose the game, instead exile this emblem, shuffle all cards you own that aren't on the battlefield into your library, then draw seven cards. Your life total becomes 40.”

Whenever you make first contact, you may tap target creature. (You make first contact the first time each turn you cast a spell with a name not in your graveyard or control already.)