msem-instigator

Archive 0 (As this enters, shuffle the top zero cards of your main library into a new face up library. Sacrifice this after the archived library is empty.)
As Undue's Study enters, shuffle your graveyard into the archived library.

Defender
{1}{W}, {T}: Tap target creature.

Wu Xing (Add effects based on the number of colors of mana spent to cast this spell.)
1 | Battle of Principles deals X damage to any target.
5 | When a creature or planeswalker dealt damage this way dies this turn, return it to the battlefield under your control.

At the beginning of combat on each of your turns, you may have target land you control become a 3/3 Elemental creature with haste until end of turn. It's still a land.
Sacrifice Seeds of New Life: Return up to two target land cards from your graveyard to your hand. Activate only as a sorcery.

Put a +1/+1 counter on target creature you control. Prevent all damage that would be dealt to that creature this turn.

Vanishing 3 (This permanent enters with three time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
When Hundred Years of Solitude enters, exile another target nonland permanent until Hundred Years of Solitude leaves the battlefield.

Return target creature to its owner's hand. Another target creature gets -6/-0 until end of turn.

Whenever Merfolk Vandal deals combat damage to a player, you may pay {U}. If you do, transform it.

Defender
When Ethereal Threshold enters, if it was cast, exile target artifact or creature. Return that card to the battlefield under its owner's control at the beginning of the next end step.

{2}, Sacrifice a creature or artifact: Hadak's Guardian deals 2 damage to any target.

When Cou Ling enters, create two 2/1 red and white Fox creature tokens.
Whenever a Fox you control deals combat damage to a player, draw a card, then you may cast an instant or sorcery card with mana value less than or equal to the damage dealt from your hand without paying its mana cost.

Solar Flare deals 3 damage to any target. You gain 3 life.

Once each turn, you may cast a creature you control from the battlefield.
(You can cast its Adventure this way.)

Whenever a player activates an ability that isn't a mana ability, Burning-Tree Shaman deals 1 damage to that player.

Attentive Glider gets +2/+2 and has flying as long as you cast an Adventure spell or a permanent you controlled explored this turn.

Flying
When Zenith of Greed enters, search your library for up to two cards named Treasure Hoard and put them onto the battlefield, then shuffle.

Refine {3}{W}{B} (You may cast this spell by sacrificing an artifact and paying the refine cost reduced by that artifact's mana value.)
When H-9K Prototype enters, if it was refined, destroy target nonland permanent.

Other Hounds you control have trample.
{R/W}, {T}: Put a +1/+1 counter on target Hound you control.

{T}: Add {G}. When that mana is used to cast a spell with mana value 5 or greater, you may untap Performer of Growth and transform it.

Target player discards a card. Until your next turn, whenever that player casts a spell, they discard a card.

Search your library for two basic land cards that don't share a land type and put them onto the battlefield tapped.
{W}{U}{B}{R}{G}, Exile The World Follows After from your graveyard: Create a 4/4 Elemental creature token that's all colors. It can't block this turn.

When Landbound Ritualist enters, you may put a land card from your hand or graveyard onto the battlefield tapped.

Equipped creature has double strike.
Whenever equipped creature attacks, 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.”)
Abilities of Idols you control that target equipped creature cost {1} less to activate.
Equip {2}{W}

Search your library for a cryptic card, reveal it, put it into your hand, then shuffle. (Artifacts, enchantments, and modal spells are cryptic.)