msem-instigator

Germinate, then creatures you control that are Saprolings or have counters on them gain indestructible until end of turn. (To germinate, put a +1/+1 counter on a creature or create a 1/1 green Saproling creature token.)

Whenever you draw a card, put a +1/+1 counter on Ontarachie Curio.
{T}, Remove a +1/+1 counter from Ontarachie Curio: Create a colorless artifact token named Lotus Petal with “{T}, Sacrifice this artifact: Add one mana of any color.”
{1}{G}: Ontarachie Curio becomes a green 2/1 Dryad creature until end of turn. (It's no longer an artifact.)

When Onward to War enters, draw a card, then choose a card name.
Whenever one or more creatures you control with the chosen name attack, look at the top four cards of your library. Put a creature or enchantment card with mana value 3 or less from among them into your hand. Put the rest on the bottom of your library in any order.

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.

Archive 6 (As this enters, shuffle the top six cards of your main library into a new face up library. Sacrifice this after the archived library is empty.)
Whenever a creature or planeswalker you control dies, you may play a card from the archived library. (You still pay its costs.)

Opalescent Heirloom enters with a charge counter on it for each color of mana spent to cast it.
Equipped creature gets +1/+1 for each charge counter on Opalescent Heirloom.
Equip—{3} or remove a charge counter from Opalescent Heirloom.

{T}: Add {U} or {R}. You lose 1 life unless you have less life than an opponent.

Search your library for a land card, reveal it, then shuffle and put that card on top. (Then exile this card. You may play the land later from exile.)

Whenever Open Road or another permanent you control enters, if it has the greatest mana value among permanents you control, you may discard a card. If you do, draw a card.

At the beginning of your upkeep, each player conjures a card named Data-Point into their hand. (It's a sorcery that costs {2} with “Draw a card.”)

Return target creature card from your graveyard to the battlefield, then rediscover a creature card. (Look at the top card of your library. You may reveal it and put it into your hand if it's a creature card. Otherwise, put it back or into your graveyard.)

For each nonland token you control, create a token that's a copy of it.

Exile two target permanents you control, then return them to the battlefield under your control.

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.

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.)

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

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.

Draw three cards, then discard two cards.

Search your library for up to six cards and exile them face down. Shuffle, then draw a card.

Enchant creature
Enchanted creature gets -3/-3.
When enchanted creature dies, its controller may scry 1.