msem-instigator

{X}{G}: Put X +1/+1 counters on target noncreature, nonplaneswalker permanent you control. It becomes an Elemental creature with base power and toughness 0/0 in addition to its other types. (This effect lasts indefinitely.)

As The Mistake enters the battlefield, choose a card name.
Activated abilities of sources with the chosen name can't be activated unless they're mana abilities.
Unveil {5} ({5}: Transform this. Unveil only as a sorcery.)

Creatures you control get +2/+0 until end of turn. Creatures you control with counters on them gain trample until end of turn.

[+1]: Add {W}{U}{B}{R}{G}.
[–1]: Exile the top three cards of your library. Until end of turn, you may play cards exiled with this permanent.
[–3]: Create a 5/5 Archon creature token that's all colors and has flying and “When this creature enters the battlefield, it deals 5 damage to any target.”

{T}: Add {C}.
{2}, {T}: Choose a color, then choose one —
• Add one mana of that color for each token you control.
• Add one mana of that color for each permanent you control with one or more counters on it.

Each planeswalker you control is an Okus in addition to its other types.
[–1]: Search your library for a planeswalker card or an Aura card with enchant planeswalker, reveal it, and put it into your hand, then shuffle.
The Paragon of Haberdashery can be your commander. If it is, it's all colors.

Creatures you control have trample, haste, and hexproof.
{2}{G}{G}: Create a 2/2 white Cat creature token.

This spell can't be countered.
Whenever a creature you control with power 5 or greater attacks alone, it deals damage equal to its power to each opponent and to each other creature and planeswalker.

Indestructible
Spells you cast from your graveyard cost {6} less to cast.
Whenever you attack, you may cast any number of target cards from your graveyard this turn. If a spell or permanent that was cast this way would be put into a graveyard, exile it instead.

Whenever The Pyleas, Siona's Pride enters the battlefield or attacks, look at the top six cards of your library. You may reveal a legendary non-Vehicle card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.
Crew 2

{T}: The next time you would draw a card this turn, instead search your library for a card, put it into your hand, then shuffle. Activate only as a sorcery.

Equipped creature gets +2/+2 and has deathtouch and lifelink.
Whenever equipped creature dies, you may exile it. If you do, return target Knight or Soldier card from your graveyard to the battlefield tapped, then attach The Roseblade to it.
Equip {2}

Once each turn, when another permanent enters the battlefield under your control, you may create a token that's a copy of that permanent, except it has no mana cost.

Trample
Creatures you control have “{T}: This creature deals 1 damage to each opponent. Activate only as a sorcery.”
At the beginning of combat on your turn, if an opponent lost 4 or more life this turn, you may have The Shadowstaff become an artifact creature until end of turn.

Creatures you control get +1/+1 and gain trample until end of turn.
Reconstruct {4}{G} (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.)

{T}: You may pay {0} rather than the mana cost of the next spell you cast this turn. Activate only if you have no cards in hand.

When The Struggle for Death enters, choose target creature you don't control. Any number of creatures you control fight that creature.
Whenever a creature dies, look at the top card of your library. You may put it into your graveyard.

Choose one or more —
• The Sun Rises deals 2 damage to any target.
• The Sun Rises deals 7 damage to target creature you control.

Deathtouch
When The Terror of Shady Cove enters the battlefield, target opponent sacrifices an artifact. If they can't, create a 3/3 green Slug creature token with deathtouch. Then repeat this process for an enchantment and a nonbasic land.

When The Third Breach enters the battlefield, discard your hand, then draw seven cards.
Creatures you control get +3/+3, have haste, and are Horrors in addition to their other types.
At the beginning of each end step, sacrifice each creature you control.

{T}: Add {C}.
{1}, {T}: Draw a card, then discard a card. Activate only if seven or more cards are in your graveyard.

Whenever you sacrifice a Clue, you lose life equal to the number of Clues you control, then investigate twice. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

[0]: Creatures you control gain haste until end of turn. Whenever a creature attacks this turn, put a loyalty counter on The Warrior Within.
[–1]: Exile the bottom two cards of your library. You may play one of them this turn.
[–6]: Untap each creature that attacked this turn. After this main phase, there is an additional combat phase.

{T}: Add {C}.
{1}, {T}, Sacrifice The Whisperwoods: Add two mana in any combination of colors.
At the beginning of each end step, if a player lost life this turn, return The Whisperwoods from your graveyard to your hand.

Whenever The Wicker Lord or another Scarecrow enters the battlefield under your control, create a 1/1 black Bird creature token with flying for each Scarecrow you control.
{4}, Sacrifice a Scarecrow: Return target artifact card from your graveyard to the battlefield.