msem-instigator

Archive 7 (As this enters, shuffle the top seven cards of your main library into a new face up library. Sacrifice this after the archived library is empty.)
As long as you control five or more creatures, you may play permanent cards from the archived library.

When Seafloor Casket enters and when you sacrifice it, target player mills two cards.
{1}{U}, Sacrifice Seafloor Casket: Draw a card.
Cycling {2} ({2}, Discard this card: Draw a card.)

{2}{U}{B}, Sacrifice a creature: Return target creature card from your graveyard to the battlefield with a finality counter on it. It gains myriad. (Whenever it attacks, for each opponent other than defending player, you may put a token that's a copy of this creature onto the battlefield tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)

Destroy target nonland permanent. You may return a card that shares a card type with that permanent from your graveyard to your hand.

Activated abilities of other permanents cost an additional “Sacrifice a permanent” to activate unless they're mana abilities.
{2}, {T}, Sacrifice Nullifier of Planar Energy: Remove all counters from target nonland permanent.

Kicker {2} (You may pay an additional {2} as you cast this spell.)
Prowess
When Merkurio's Opus enters, if it was kicked, draw two cards, then discard two cards.

Put three -1/-1 counters on target attacking or blocking creature.

Flying (This creature can't be blocked except by creatures with flying or reach.)
Heavensent Emissary enters with a +1/+1 counter on it for each other creature with flying you control.

Poisonous 1 (Whenever this creature deals combat damage to a player, that player gets a poison counter.)
Blade of the Serpent gets +1/+1 as long as an opponent is poisoned.

Whenever an artifact enters or leaves the battlefield under your control, you gain 1 life.

Trample
When Pernicious Primavore enters or dies, destroy up to three target artifacts and/or enchantments.

Flying (This creature can't be blocked except by creatures with flying or reach.)
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

When this enchantment enters, create a 1/1 white Peasant creature token.
{B/R}, Sacrifice a creature: Exile the top card of your library. You may play that card this turn.

{1}, {T}, Sacrifice two or more nonland permanents: Return target creature card from your graveyard to the battlefield. If permanents with total mana value 4 or greater were sacrificed this way, draw a card.

Advance {2}{R} (Cast this for {2}{R} to advance it as it enters. {2}{R}: Advance this as a sorcery.)
Haste
Whenever Soulblade Warrior advances, it gets +2/+0 until end of turn.

Fortune's Fusillade deals X damage divided as you choose among any number of targets, where X is the number of Pirates and Rogues you control plus the number of instant and sorcery cards in your graveyard.

You may have Ligneous Enormity assign its combat damage as though it weren't blocked.
Madness {3}{G}{G} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Flash (You may cast this spell any time you could cast an instant.)
When Majestic Hippocamp enters, target creature gets -2/-0 until end of turn.

Whenever you cast a spell, you may pay 3 life. If you do, draw a card.

As an additional cost to cast Reality Reversal, return X nonland permanents you control to their owners' hands.
Return X plus one target nonland permanents to their owners' hands.

[+2]: Create a 3/3 red Wurm creature token.
[–2]: Up to three target creatures each get +2/+2 until end of turn. Bessie deals 2 damage to each of up to three target creatures.
[–9]: You get an emblem with “Creatures you control have base power and toughness 7/7 and have indestructible.”

Counter target spell unless its controller pays {1}.

Flying
When T'nege, Skyguard enters, exile another target creature you control until T'nege leaves the battlefield. If you do, exile target creature an opponent controls until T'nege leaves the battlefield.

Heroic — Whenever you cast a spell that targets Thassa's Shoreguards, tap target creature an opponent controls. It doesn't untap during its controller's next untap step.
Whenever Thassa's Shoreguards deals combat damage to a player, draw a card.

Menace (This creature can't be blocked except by two or more creatures.)
Sacrifice another creature: Stingbrood Warlord gains deathtouch until end of turn.