msem-instigator

Destroy target artifact. Scry 1.

At the beginning of your upkeep, reveal the bottom card of your library. You may cast it if it's a creature card. Otherwise, exile it.

Trample
Whenever Openmaw Demon or another Azra or Demon you control enters, you may exile target card from a graveyard.

Opera House enters tapped.
When Opera House enters, add one mana of any color.
{T}, Sacrifice Opera House: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Search your library for a creature or sorcery card, put it into your graveyard, then shuffle.
Reconstruct {2}{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.)

Converge — When Operations Manager enters, create X 1/1 colorless Servo artifact creature tokens, where X is the number of colors of mana spent to cast Operations Manager.

Lifelink
Whenever Operative BABY attacks or you cast a black or red spell, create a 1/1 blue Elemental creature token with flying.

Menace
Whenever Operative GINGER attacks or you cast a blue or white spell, Operative GINGER deals 1 damage to any target.

Flash
Whenever Operative POSH attacks or you cast a green or red spell, exile up to one target nontoken permanent. Return that card to the battlefield under its owner's control at the beginning of the next end step.

Deathtouch
Whenever Operative SCARY attacks or you cast a green or white spell, you may draw a card. If you do, you lose 2 life.

Ward {3}
Whenever Operative SPORTY attacks or you cast a blue or black spell, put a +1/+1 counter on Operative SPORTY.

Ophan Titan gets +3/+3 as long as there are no nonland cards in your graveyard.
Morph {1}{G} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Lifelink (Damage dealt by this creature also causes you to gain that much life.)
When Ophelia's Neophyte enters, you may have another target creature you control gain lifelink until end of turn.

Once each turn, you may pay {U} rather than pay the mana cost for a blue spell you cast.

When Ophidian Oracle enters, draw a card, then abound. (To abound, you may cast a spell that costs less than this from your hand without paying its mana cost.)
Recite {2}{G}{G} (You may cast this creature from your graveyard for its recite cost. If you do, exile it when it enters or if it would leave the battlefield.)

When Ophorio Scavenger 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.”)
Ophorio Scavenger gets +1/+1 as long as you control three or more artifacts.

{T}: Add {G}. If you control an attacking creature, add one mana of any color instead.

Voracious 2 (As this enters, you may sacrifice up to two artifacts and/or creatures. This creature enters with that many +1/+1 counters on it.)
When Opportunistic Beast enters, destroy up to one target creature that was dealt damage this turn.

Bleed {1}{B/R} (You may cast this spell for its bleed cost if an opponent has lost life this turn.)
Haste
When Opportunistic Raiders enters, if it's your main phase, after this phase, there is an additional combat phase followed by an additional main phase.

Target creature gets -4/-4 until end of turn.
Civilized — Draw a card if you control an artifact, a creature, and an enchantment.

Enchant creature
Enchanted creature can't attack or block unless its controller pays {3}.
Activated abilities of enchanted creature cost {3} more to activate.

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

Scry 1.
Draw a card.

Whenever you cast your first instant or sorcery spell each turn, create a Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)

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.