msem-instigator

At the beginning of your upkeep, you gain 1 life. Then each opponent may give themselves a poison counter. For each opponent who doesn't, create a 2/2 white Angel creature token with flying.

Flying (This creature can't be blocked except by creatures with flying or reach.)
Heavensent Emissary enters with a +1/+1 counter on it for each other creature with flying you control.

When Heedless Lovers enters, you may return target Citizen card from your graveyard to your hand.
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Equipped creature gets +1/+1 for each card in your hand.
Equip {3}

At the beginning of combat on your turn, you may attach any number of Equipment you control to target creature you control.

When Heirloom Seeker enters, you may search your library for an Equipment card, reveal it, then shuffle and put that card on top of it.
Heirloom Seeker has first strike as long as it's equipped.

Rogues and Pirates you control have haste.
Whenever one or more creatures you control deal combat damage to a player, exile the top card of your library. You may play that card this turn.

Destroy target artifact or land. If a land was destroyed this way, its controller may search their library for a basic land card, put it onto the battlefield tapped, then shuffle.
Agonize (You may cast this card from your graveyard by putting a -1/-1 counter on a creature you control in addition to paying its other costs. Then exile this card.)

Whenever you cast a noncreature spell, you may put a progress counter on Hellbent Speed.
[PROGRESS 2+] Noncreature spells you cast cost {1} less to cast. This effect can't reduce the amount of mana a spell costs to cast to less than one mana.
[PROGRESS 6+] Whenever you cast a noncreature spell, draw a card.

Menace
{1}{B}{R}: Creatures you control get +1/+0 until end of turn.

Hellkite's Decree deals 3 damage divided as you choose among one, two, or three target creatures and/or planeswalkers.
Cycling {2} ({2}, Discard this card: Draw a card.)

{T}: Add {C}.
{T}, Reappropriate: Add {B} or {R}. (To reappropriate, exile exactly two cards from your hand and/or graveyard.)

Equipped creature has hexproof.
Whenever equipped creature dies, draw a card.
Equip {2}

Equipped creature has “{T}: Target attacking creature gets +1/+1 until end of turn.”
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Whenever a nontoken creature you control dies, create a 1/1 colorless Spirit creature token with flying.

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Put a +1/+1 counter on target creature you control. It gains vigilance until end of turn.
III — Target creature you control gets +2/+2 and gains flying, vigilance, and lifelink until end of turn.

Elemental, instant, and sorcery spells you cast cost {1} less to cast.

When Herald of Darkness enters, destroy up to one target creature with mana value 3 or less.

Whenever Herald of Purity is dealt damage, it deals that much damage to any target.
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Whenever another nontoken creature you control dies, create a 1/1 green Saproling creature token.
{B}{G}, {T}, Sacrifice a creature: Return target permanent card from your graveyard to your hand.

Rapport — Whenever Herald of the Hunt and at least one other creature you control become tapped, nourish 1. (To nourish 1, either put a +1/+1 counter on this creature or create a 1/1 white Citizen creature token.)

Encourage ({T}: Another target creature you control gets +1/+1 until end of turn. Encourage only as a sorcery.)
Whenever a creature deals combat damage to a player, if it was encouraged by Herald of the White Orchid this turn, create a 1/1 white Soldier creature token.

You may cast Heralds of Shikai from your graveyard as long as a creature an opponent controls died this turn.

Beckon Ox {1}{W} ({1}{W}: This enchantment permanently becomes an Ox creature in addition to its other types.)
Vigilance
Whenever a creature or another enchantment you control enters, you gain 1 life.

When Heretic's Vow enters, create two 1/1 white Cleric creature tokens with lifelink.
Once each turn, when you gain life, you may put a +1/+1 counter on target creature you control.