msem-instigator

Whenever another creature you control enters, put your choice of a +1/+1 counter, a trample counter, or a haste counter on it.

When Street Performer enters, create a 2/1 blue Illusion creature token with “When this creature becomes the target of a spell or ability, sacrifice it.”

Choose one or both —
• Audition for green. (Create a 1/1 Construct Actor creature token, a Scout Role giving 2/3 and vigilance, or a Warrior Role giving 3/2 and trample. Roles replace older ones.)
• Target creature you control fights target creature you don't control.

You may have Strikebreaker enter as a copy of a non-Aura enchantment you control, except it's a 2/2 Construct Actor creature in addition to its types.

Creatures you control get +2/+2 and gain trample until end of turn. If you cast this spell from exile, creatures you control get an additional +2/+2 until end of turn.
Prophecy {2}{G}{G} (Once each turn, you may exile a card with prophecy as you reveal it. When you do, you may cast it for its prophecy cost as long as it's exiled.)

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Create two 1/1 colorless Construct Actor creature tokens.
II, III — Creatures you control gain flying until end of turn. Whenever one or more of them deals combat damage to a player this turn, draw a card.
​

When Swiftwheel Slayers enters, audition for red. (Create a 1/1 Construct Actor creature token, a Warrior Role giving 3/2 and trample, or a Wizard Role giving 2/2 and prowess. Roles replace older ones.)
Token creatures you control have haste.

(As this Discovery enters and after your draw step, add a progress counter. Stop after you've discovered.)
Archive 6 (As this enters, shuffle the top six cards of your main library into a new face up library. Sacrifice this after the archived library is empty.)
Draw a card from each of your libraries.
discover — When you draw the last card from the archived library, create a 4/4 blue Sphinx Wizard creature token with flying.

Enchant creature
When Sythian Scripture enters, put two +1/+1 counters on enchanted creature.
Enchanted creature gets +1/+1 and has indestructible and lifelink if you controlled a white legendary creature or planeswalker as you cast Sythian Scripture.

Whenever you attack, you may draw a card. If you do, discard a card.

Haste
Whenever Tailor of Terror attacks, you may exile a creature card from your graveyard. If you do, put a +1/+1 counter on Tailor of Terror.

Create two 1/1 black Rat Pirate creature tokens.
Whenever two or more creatures you control deal combat damage to a player, you may pay {2} and exile Take All You Can Carry from your graveyard. If you do, create two Treasure tokens.

Target creature you control gets +1/+1 and gains lifelink until end of turn. It fights target creature you don't control.

Choose one or both —
• Target player searches their library for a basic Plains card, reveals it, put it into their hand, then shuffles.
• Exile target permanent you control, then return it to the battlefield under its owner's control.

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Create a Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)
III — For each color, return up to one target creature card of that color from your graveyard to your hand.
​

Tears of Samang deals 3 damage to each creature and each player. If an opponent would be dealt damage this way, you may have Tears of Samang deal 3 damage to a planeswalker they control instead.

When Tempered Ankulim enters, choose one —
• You gain 2 life.
• Each opponent loses 2 life.

{T}: Add one mana of any color.
{X}: Terracotta Idol becomes a Spirit artifact creature with base power and toughness X/X until end of turn. Activate only as a sorcery.

Flying
Territorial Drake has hexproof as long as it's untapped.
Whenever Territorial Drake becomes tapped, scry 2.
Whenever Territorial Drake becomes untapped, draw a card.

Kicker {4}{U}{U} (You may pay an additional {4}{U}{U} as you cast this spell.)
Return target nonland permanent to its owner's hand. If this spell was kicked, create an 8/8 blue Kraken creature token with trample.

First strike
Thailen, Heir to Daeland's power is equal to the number of other attacking or blocking creatures you control.

Flying, lifelink
Whenever you gain life, each opponent loses 1 life.
{4}{B}{B}: Create a 1/1 black Vampire creature token with lifelink for each nontoken creature that died this turn.

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Audition for black. (Create a 1/1 Construct Actor creature token, a Cleric Role giving 2/2 and lifelink, or a Warlock Role giving 2/1 and flying. Roles replace older ones.)
III — Until end of turn, if a creature you don't control would die, instead exile it and that creature's controller loses 2 life.
​

Thawing Valley enters tapped unless you control a basic land.
{T}: Add {G} or {U}.

Reconstruct {4}{B}{B}{B} (You may cast this from your graveyard for its reconstruct cost reduced by the mana value of a permanent you sacrifice as you cast it this way. Then exile this.)
Destroy all creatures. If The Afterlife Takes Its Due was reconstructed, create an X/X black Zombie Horror creature token, where X is the number of creature cards that have been put into graveyards this turn.