msem-instigator

Reveal the top five cards of your library. Put one of those cards into your hand. Target opponent chooses two of those cards. Exile the chosen cards, then put the rest into your hand.

Whenever you cast a spell, sacrifice a permanent and draw a card.
Exile three cards from your graveyard: Counter target noncreature spell unless its controller pays {1}.

At the beginning of your end step, for each opponent, destroy up to one target creature that player controls with power less than or equal to the amount of life that player lost this turn.
{3}{R}: Selezzar, Tyrant of Endak deals 2 damage to each opponent.

Create a 1/1 colorless Construct artifact creature token. If you control an artifact, create two of those tokens instead.

Enchant creature
When Selfish Epiphany enters, search your library for a card and put that card into your hand. Then shuffle.
Enchanted creature has indestructible and can't be sacrificed.

Whenever a Survivor you control dies, you draw a card and you lose 1 life.

Instant and sorcery spells you cast cost {1} less to cast.
Rapport — Whenever Selma Lappowen and at least one other creature you control become tapped, exile the top card of your library. Until end of turn, you may play that card.

When Seluriel's Blessing enters, put a +1/+1 counter on each creature you control.
Creatures you control enter with an additional +1/+1 counter on them.
Creatures you control with counters on them have vigilance and indestructible.

[+1]: You gain 1 life. Put a +1/+1 counter on up to one target creature.
[–3]: Exile target creature. Its controller gains life equal to its power.
[–8]: You get an emblem with “Creatures you control get +1/+1 and have double strike and lifelink.”

Until end of turn, target creature you control gains double strike and trample. Sacrifice it at the beginning of the next end step.
Draw a card.

Whenever a quest counter is put on a permanent you control, upgrade Selvar, the Seeker. (Give it one of the listed counters it doesn't already have.)
• +1/+1
• First strike
• Vigilance
• Reach
• Trample
• Lifelink

Deathtouch
Whenever another creature you control dies, each opponent loses 1 life.
{2}{W}: Create a 1/1 colorless Servo artifact creature token.

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.

At the beginning of your draw step, draw an additional card and you lose 1 life. Then if you have six or fewer cards in hand, sacrifice a creature.

Death knell — Put a +1/+1, flying, lifelink, or menace counter on Senn, the Haunting Gaze, then trigger a death knell of another permanent you control. (As a creature you control dies, trigger one death knell of that creature or another permanent you control.)

When Sensational Festivities enters or at the beginning of your upkeep, you may draw a card. If you do, each opponent may draw a card, then discard a card.

Untap all permanents you control during each other player's untap step.

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.

Sentinel of the Highlands has hexproof as long as it's embattled. (A creature is embattled if it has a counter on it or has a permanent you control attached to it.)

Equipped creature gets +2/+0. As long as it's a Knight, it has first strike.
Equip {1}{W}

Flying, vigilance
Whenever Sepulchral Guide attacks, prevent all combat damage that would be dealt to another target creature you control this turn. If that creature has two or more counters on it, untap it.

Deathtouch, menace
As long as you control another Knight creature, Ser Joffrey, Plague of Nines and other Knight creatures you control have first strike.

Trample
Ser Malcomn's power and toughness are each equal to the number of nonbasic lands your opponents control.

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.)