msem-instigator

{3}: Sellsword Contraption becomes the creature type of your choice until end of turn.

When you cast Senaturian Centurion, reveal cards from the top of your library until you reveal a creature card with mana value 2 or less. Copy that card, then put the revealed card into your hand. You may cast the copy without paying its mana cost. Put the revealed cards on the bottom of your library in a random order.

When Sending Stones enters, harmonize twice. (To harmonize, trigger up to one harmony of a permanent you control.)
If you would harmonize, you may trigger a harmony of a permanent card in your graveyard instead.

{2/U}, {T}: Target creature gets -4/-0 until end of turn.

Lionize {1}{W} ({1}{W}, Exile this card from your hand: Put a +1/+1 counter on target creature and it gains the following ability until end of turn. You may cast this card on a later turn from exile.)
Flying

Soldiercycling {1}{W}, Wizardcycling {1}{U}, Zombiecycling {1}{B}, Warriorcycling {1}{R}, Elfcycling {1}{G} ({1}{G}, Discard this card: Search your library for an Elf card, reveal it, and put it into your hand, then shuffle.)
Sentinel of Latter Days is every creature type as long as it's in your library.

Whenever Ser Wayver, the Broken Hour attacks, each opponent loses 2 life and you gain that much life.
When Ser Wayver dies or is countered, exile it with three time counters on it and it gains suspend. (At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast this card without paying its mana cost. It has haste.)

Draw two cards. If you control an Angel, draw three cards instead.

Enspirit (As you cast this spell, you may exile a nonenchantment creature you control until this leaves the battlefield or fails to resolve. Reduce this spell's cost by the exiled card's mana value.)
{T}: Add {G}{G}.

Encourage ({T}: Another target creature you control gets +1/+1 until end of turn. Encourage only as a sorcery.)
Whenever Serul Cove Escort encourages a creature, that creature gains flying until end of turn.

When Servant of Armageddon dies, destroy all creatures.

[+1]: Remove all counters from target permanent.
[+1]: Each opponent discards a card.
[–2]: Exile target creature or planeswalker card from your graveyard with mana value less than or equal to the number of lands you control. If you do, create a token that's a copy of it.
[–7]: Each opponent gets an emblem with “At the beginning of your upkeep, you lose 7 life unless you sacrifice seven permanents.”

[+1]: Distribute two +1/+1 counters among any number of target creatures you control.
[–1]: Create two 1/1 white Monk creature tokens.
[–6]: Until your next turn, you choose which creatures attack or block and how those creatures attack or block.

[+1]: Create a 1/1 white Warrior creature token with lifelink. You gain 1 life.
[–2]: Put two +1/+1 counters on target creature. It gains double strike until end of turn.
[–7]: Choose up to three creatures, then destroy the rest.

(Choose only one work as a sorcery to add its ability.)
When Seto's Private Collection enters, creatures you control get +2/+1 until end of turn.
{1}{R}: Bloodline
Attacking creatures you control have first strike.
{2}{W}: Hope's Savior
Attacking creatures you control have lifelink.

Destroy all creatures.

Settle the Dust deals 4 damage to each tapped creature.

(As an Encounter enters, choose an opponent to protect it. You and others can attack it. When defense counters are removed, create a 0/0 Army token if you don't control one, then put that many +1/+1 counters on a Army you control.)
When Settling of Nizev enters, look at the top four cards of an opponent's library, exile two of them, and put the rest on the bottom of their library in a random order. You may play those cards for as long as they remain exiled, and mana of any type can be spent to cast them.

For each player, exile target creature or planeswalker they control.

Destroy target creature. If an opponent lost life this turn, that creature's controller mills five cards.

Destroy target creature or planeswalker. If you controlled a black legendary creature or planeswalker as you cast this spell, that permanent's controller loses X life and you gain X life, where X is that permanent's mana value.

When Severed Hands enters, surveil 2.
Whenever one or more cards leave your graveyard, tap target creature an opponent controls and put a stun counter on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)

[+1]: Create a 1/1 green Scout creature token. If you control six or more lands, also create a 1/1 white Bird creature token with flying.
[–1]: Reveal the top card of your library. If it's a land card, put it onto the battlefield. Otherwise, put it into your hand.
[–5]: You get an emblem with “Whenever each permanent you control becomes tapped for the first time each turn, untap it.”

When Shackled Memories enters, return target instant or sorcery card from your graveyard or card with flashback you own from exile to your hand.
Invocation — Whenever you spend four or more mana to cast a spell or activate an ability during your turn, create a 1/1 white Spirit creature token with flying.

All creatures get -3/-3 until end of turn.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, if a creature would die this turn, exile it instead.