msem-instigator

I — Create a 1/1 red Hound creature token.
II — Create a 4/4 green Rhino Warrior creature token with trample.
III — You may have two target creatures you control fight. If you do and exactly one survives, put four +1/+1 counters on that creature.

Tracking Party enters with a +1/+1 counter on it.
{T}, Remove a +1/+1 counter from Tracking Party and exert it: Destroy target artifact or enchantment. (An exerted creature won't untap during your next untap step.)

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Audition for blue. (Create a 1/1 Construct Actor creature token, a Wizard Role giving 2/2 and prowess, or a Warlock Role giving 2/1 and flying. Roles replace older ones.)
III — Whenever a creature you control deals combat damage to a player this turn, draw a card.
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At the beginning of combat on your turn, you may have Regurgitator Ooze consume. If you do, it gets +2/+2 until end of turn. (To consume, sacrifice another creature or exile a creature card from your graveyard.)
When Regurgitator Ooze dies, return a card exiled with it to its owner's hand.

Return target creature you control to its owner's hand. You gain life equal to its power.

This spell costs {X} less to cast, where X is the greatest power among creatures you control.
{1}: Target creature in Indomitable Anchorite's pack gains indestructible until end of turn. (Two or more creatures you control with equal power are in a pack.)

This spell can't be countered.
Creatures you control have ward {2}. (Whenever one becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
When Natural Philosopher enters, you gain 2 life for each creature you control with power 4 or greater.

Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
Masked Lancer has first strike as long as it's attacking.
Whenever Masked Lancer mentors a creature, that creature gains first strike until end of turn.

[+2]: You may discard a card. If you do, draw two cards.
[–3]: Return target creature card from your graveyard to the battlefield. It gains haste. Return it to your hand at the beginning of the next end step.
[–7]: Discard your hand, then draw seven cards. You may put an Edarna planeswalker card from your hand or graveyard onto the battlefield.

Draw a card, then each player draws a card.

Whenever Gravelocked Seeker blocks, return target creature card from your graveyard to the battlefield blocking a creature that's attacking you (even if that block would be illegal).

Enchant creature
Enchanted creature gets +3/+1.

Haste, prowess
Wanderlust — When Spitfireling enters, if you control four or more differently named lands, create two 1/1 red Elemental creature tokens with prowess and haste.

Return up to one target creature card and up to one target noncreature permanent card with total mana value 4 or less from your graveyard to the battlefield.
Exile Beckon the Damned.

Target creature you control gets +1/+0 until end of turn. It fights up to one target creature you don't control. (Each deals damage equal to its power to the other.)

Grizzled Den enters tapped.
{T}: Add {R} or {G}.
{3}{R}{G}: Until end of turn, Grizzled Den becomes a Bear creature with trample in addition to its other types.
Scavenge {4}{R}{G}

Menace
Crew 3 (Tap any number of creatures you control with total power 3 or greater: This Vehicle becomes an artifact creature until end of turn.)

{T}: Add one mana of any color in your commander's color identity.

When Onya the Gilded dies, search your library for a planeswalker card with a different name, reveal it, put it into your hand, then shuffle.
[–1]: Draw up to two cards. For each of those cards, pay 1 life or discard a card.
[–2]: Creatures you control get +1/+1 until your next turn.
[–3]: Onya the Gilded deals 3 damage to any target and you gain 3 life.

Flash
When Augmented Spawn enters, create a 1/1 blue Merfolk creature token for each Island you control.
{U}, Sacrifice a Merfolk: Augmented Spawn gains hexproof until end of turn.

Untap target creature and gain control of it until end of turn. That creature gains haste until end of turn.

Deathtouch
Attacking creatures you control with deathtouch get +2/+0.

Trample
Stampede — Whenever Thoctar Yearling and a creature with greater power attack, put a +1/+1 counter on Thoctar Yearling.

First mate—Your starting deck contains no creature cards. (If this card outside the game is your chosen first mate, you may swap it with a card in your opening hand.)
Prowess
Whenever Garth attacks, look at the top card of your library. If it's an instant or sorcery card, you may cast it. (You still pay its costs.)

Slipstream (This creature can't be blocked as long as only creatures with slipstream are attacking.)
Sacrifice Bonetooth Darter: Counter target instant, planeswalker, or sorcery spell unless its controller pays {1}.