msem-instigator

{1}{W}, {T}: Aetherize target creature you control. (To aetherize, create a token that's a copy of it, then exile that token.)

When Experienced Team enters, choose one —
• Create a 4/2 white Bear creature token.
• Create a 2/4 red Snail creature token.
• Create a 2/2 white Bird creature token with flying.

Flying, lifelink
When Daystrider Pegasus enters, exile another target non-Pegasus permanent you control, then return it to the battlefield under its owner's control.

When Daybreak enters, you gain 3 life.
Creatures can't attack you or planeswalkers you control unless their controller pays {1} for each of those creatures.

Exile all creatures. Exile Cycle of Creation with X genesis counters on it, where X is the number of creatures exiled this way.
Whenever you cast a spell, if Cycle of Creation is in exile, you may remove a genesis counter from it. If you do, create a 1/1 white Human creature token.

When Chiseled Familiar enters, draw a card.
Sacrifice Chiseled Familiar: You gain 2 life.

Flying, vigilance
At the beginning of your upkeep, if you control four or more Plains, put a +1/+1 counter on each other creature you control.

Motivate 2 (When this creature enters, you may motivate target creature with less power than this by putting two +1/+1 counters on it.)
{1}{W}: Target creature with a +1/+1 counter on it gains lifelink until end of turn.

Each planeswalker you control is an Okus in addition to its other types.
[–1]: Search your library for a planeswalker card or an Aura card with enchant planeswalker, reveal it, and put it into your hand, then shuffle.
The Paragon of Haberdashery can be your commander. If it is, it's all colors.

First mate — Each nonland card in your starting deck has “+1/+1 counter” or “harmonize” in its printed rules text. (If this card outside the game is your chosen first mate, you may swap it with a card in your opening hand.)
Once each turn, if one or more +1/+1 counters would be put on a permanent you control, you may put twice that many of those counters on it instead.
Once each turn, if you would trigger a harmony ability of a permanent you control, you may have that ability trigger twice instead.

First mate — Twelve or more cards in your starting deck are Dragons or have “Dragon” in their printed rules text. (If this card outside the game is your chosen first mate, you may swap it with a card in your opening hand.)
Dragon spells you cast cost {1} less to cast.
Whenever Ashe attacks, it deals X damage to any target, where X is the number of Dragons you control.

First mate — Each nonland card in your starting deck is an artifact, a Pirate, or has “artifact,” “Treasure,” or “Pirate” in its printed rules text. (If this card outside the game is your chosen first mate, you may swap it with a card in your opening hand.)
Whenever Tinbeard of the Brine attacks, each opponent loses X life and you gain X life, where X is the number of artifacts you control plus the number of Pirates you control.

First mate — Twelve or more cards in your starting deck have “gain control” or “exchange control” in their printed rules text. (If this card outside the game is your chosen first mate, you may swap it with a card in your opening hand.)
Dr. Telsi of the Ark can't be blocked.
Dr. Telsi gets +1/+1 for each permanent you control but don't own.

First mate — Each land card in your starting deck has a different name. (If this card outside the game is your chosen first mate, you may swap it with a card in your opening hand.)
Lifelink, vigilance
Asabeth of the Intrepid's power and toughness are each equal to the number of lands you control.

First mate—Your starting deck contains twelve or more creature cards and they all share a creature type. (If this card outside the game is your chosen first mate, you may swap it with a card in your opening hand.)
As Adam of the Ironside enters, choose a creature type. Adam becomes that type.
Adam gets +1/+1 for each other creature you control of the chosen type.

This spell can't be countered.
Polis's Demise deals 5 damage to each creature. Destroy all artifacts.

First mate—Your starting deck contains one or more cards of exactly each color and each color pair. (If this card outside the game is your chosen first mate, you may swap it with a card in your opening hand.)
During each of your turns, you may cast a card of each color from your graveyard. If a spell cast this way would be put into your graveyard, exile it instead.

Artifact vision (Whenever this or another artifact you control enters, reveal the top card of your library. Then you may put that card into your graveyard.)
Whenever Mechanomind Researcher envisions an artifact card, put a +1/+1 counter on it.

Flying
Whenever Phantasmal Owl attacks, it gets +1/+1 until end of turn for each other creature you control with flying.

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Exile target nonland permanent you don't control until Waltz on a Nimbus leaves the battlefield.
II — Create a 1/1 white Soldier creature token with “This creature gets +1/+1 for each enchantment you control.”
III — Search your library for a non-Saga enchantment card and reveal it. You may cast that card. Then shuffle.

You may pay {B} and 4 life rather than pay this spell's mana cost.
Target creature gets -5/-5 until end of turn.

Deepdrinker's Domain enters tapped.
{T}: Add {U}.

Flash
When Cephalovorous Flukes enters, counter target spell or ability that targets you or a permanent you control.

When Dawn Silhouette enters, you may exile target creature not named Dawn Silhouette you control. Return that card to the battlefield under your control at the beginning of the next end step.
Mirage {1}{W} (You may cast this spell as though it had flash for its mirage cost. If you do, sacrifice it at the beginning of the next cleanup step.)

Whenever you draw a card, put a dream counter on Stargazing.
Remove seven dream counters from Stargazing and exile it: Shuffle your hand and graveyard into your library, then draw seven cards.