msem-instigator

Whenever an opponent draws a card, you may draw a card.

Flying
When Cerulean Sovereign enters, you may return target creature an opponent controls or instant or sorcery card in your graveyard to its owner's hand.

Flying
When Aven Merchant enters, create a Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)

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.

This spell costs {1} less to cast for each storied permanent you control. (Enchantments and legendary permanents are storied.)
Counter target spell.
Draw a card.

Flying
Warden of Harshapal Tower's power and toughness are each equal to the number of creatures you control.

Vigilance
Whenever Underpass Sentinel enters or attacks, you may put a +1/+1 counter on another target creature you control without one.
Sacrifice Underpass Sentinel: Embattled creatures you control gain hexproof and indestructible until end of turn. (A creature is embattled if it has a counter on it or a permanent you control attached to it.)

Whenever a creature you control deals combat damage to a player, if it has no +1/+1 counters on it, put a +1/+1 counter on it. You gain 1 life.

Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
{2}{W}{W}, Return an unblocked attacking creature you control to its owner's hand: Create a 4/4 white Angel creature token with flying that's tapped and attacking.

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.

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.

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Create two 1/1 white Human creature tokens.
II — Put a vigilance counter on target creature you control. It becomes a legendary God in addition to its other types.
III — Exile target creature an opponent controls that's a God or that has power 4 or greater.

When Red-Crowned Admiral enters, 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.”)
Each creature you control with a +1/+1 counter on it has flying.

When Polytheism enters, return up to four target permanent cards not named Polytheism from your graveyard to the battlefield. They become 4/4 God creatures in addition to their other types.
Gods you control have indestructible.

When Ideologize enters, exile target creature an opponent controls and each other permanent with the same name that player controls. When Ideologize is no longer on the battlefield, return a card exiled with it to the battlefield under its owner's control.

Create two 1/1 white Cleric creature tokens with lifelink.

Choose two —
• Create two 1/1 white Soldier creature tokens.
• Creatures you control get +1/+1 until end of turn.
• You gain 5 life.
• Choose a creature. It gains indestructible until end of 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.

Whenever another nontoken permanent you control enters, create a Food token.
At the beginning of each end step, put X +1/+1 counters on up to one target creature, where X is the amount of life you've gained this turn.

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.

Each other Okus planeswalker you control enters with two additional loyalty counters on it.
[–2]: Create a 2/2 white Knight creature token with vigilance.

Each player chooses a legendary permanent from among the nonland permanents they control, then sacrifices the rest.

Until end of turn, you can't lose the game, your opponents can't win the game, and your life total can't change.

Flying, first strike, lifelink

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