msem-instigator

Creatures can't attack you unless their controller pays {3} for each of those creatures.

When Opulent Proprietor enters, you may search your library and/or graveyard for an Aura, Aurashaper, Equipment, or Vehicle card, reveal it, and put it into your hand. If you search your library this way, shuffle.

(Activate each submodule once as a sorcery. When this enters, activate one submodule for free.)
{W}{W}{W}: Purpose
Create three 1/1 white Spirit creature tokens with flying.
{W}{W}{W}: Justice
Exile target nonland permanent you don't control until Order Module leaves the battlefield.
{W}{W}{W}: Unity
Order Module gains “Creatures you control get +1/+1.”

Identity — When Order's Anointer enters, if you control at least two other creatures that share a creature type with it, creatures you control get +1/+1 until end of turn.

Oreskos Warden has lifelink as long as you control an enchantment.

Your opponents play with the top card of their library revealed.
Your opponents can't cast spells during your turn.
You may play lands and cast spells from the top of an opponent's library during your turn.

{2}{W}: Ornate Legionnaire gains first strike until end of turn.

Vigilance
You may look at the top card of your library any time.
Whenever you cast a creature spell from your hand, you may cast the top card of your library without paying its mana cost if it's a creature card with lesser mana value.

At the beginning of your upkeep, scry 1, then you gain 1 life.

Flying, vigilance
Orzhov Benefactor can't attack or block unless you pay {1} for each debt counter on it.
At the beginning of your upkeep, put a debt counter on Orzhov Benefactor.
{2}: Remove a debt counter from Orzhov Benefactor.

Whenever you make first contact, Oscuran Wingmate gains flying until end of turn. (You make first contact the first time each turn you cast a spell with a name not in your graveyard or control already.)

Exile target nontoken permanent you control, then return that card to the battlefield under its owner's control.

When Oshiruko Purifier enters, create a 2/2 colorless Spirit creature token.
Colorless creatures you control have lifelink.

Distorted (This creature can be blocked by tapped creatures but not untapped creatures.)

Distorted (This creature can be blocked by tapped creatures but not untapped creatures.)
Oslyd Heretic gets +1/+1 as long as you control no other creatures.

When Ostracizer Orb enters, exile target nonartifact, nonland permanent until Ostracizer Orb leaves the battlefield.

Create X 1/1 blue Elemental creature tokens with flying.
Augmented — If you've spent {W}{U}{B}{R}{G} to cast spells this turn, creatures you control gain haste and vigilance until end of turn.

Exile any number of target creatures you control. At the beginning of the next end step, return to the battlefield tapped each creature card exiled this way and each creature card put into your graveyard from the battlefield this turn.

Enchant player
At the beginning of enchanted player's upkeep, they tap an untapped creature they control.

Exile target creature. That creature's controller creates a 1/1 blue Elemental creature token with flying.

{1}{W}, Exile Outcast of the Folded Fan from your graveyard: Create a 1/1 white Bird creature token with flying. Activate only as a sorcery.

Outer Wall Guard enters with a +1/+1 counter on it if you gained life this turn.

Destroy target attacking or blocking creature.

Vigilance, lifelink

Flying
Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
Whenever Outrider Captain attacks, search your library for a creature card with mana value 1 or less, put it onto the battlefield tapped and attacking, then shuffle.