msem-instigator

Destroy target creature. Then if there are ten or more cards in your graveyard, return target creature card from your graveyard to your hand.

Flying
Other Vampire creatures you control get +1/+0 and have menace.

Flying, lifelink
Whenever you gain life, each opponent loses 1 life.
{4}{B}{B}: Create a 1/1 black Vampire creature token with lifelink for each nontoken creature that died this turn.

Enchant creature you control
When Thassa's Benefaction enters, scry 2.
Enchanted creature gets +1/+0 and has flying.

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.

{5}{U}{U}: Thassa's Tidebringer can't be blocked this turn. This ability costs {1} less to activate for each creature you control with a counter on it.

Indestructible
As long as your devotion to blue is less than five, Thassa isn't a creature.
At the beginning of each combat, you may tap or untap another target nonland permanent.
{2}{U}: Create a 1/1 blue Merfolk Rogue creature token with “{T}: Draw a card, then discard a card.”

Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Thawing Valley enters tapped unless you control a basic land.
{T}: Add {G} or {U}.

Your opponents play with their hands revealed.
Whenever you cast a spell with the same name as a card in an opponent's hand, draw two cards.

{T}: Add {C}.
{5}, {T}, Sacrifice The Aetherite Saloon: Each player discards their hand and draws seven cards.

Reconstruct {4}{B}{B}{B} (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.)
Destroy all creatures. If The Afterlife Takes Its Due was reconstructed, create an X/X black Zombie Horror creature token, where X is the number of creature cards that have been put into graveyards this turn.

Once each turn, if a triggered ability of another legendary permanent you control would trigger, you may have it trigger an additional time.

At the beginning of the next end step, create X 1/1 white Spirit creature tokens with flying, where X is the number of creatures that died this turn.
Reconstruct {2}{W}{B} (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.)

Menace
When The Anguilahydra enters, draw X cards and put X +1/+1 counters on The Anguilahydra, where X is the number of enchantments you control.

Haste, prowess
Whenever you cast a noncreature spell, journey. (To journey, exile the top card of your library face up. Whenever a creature you control deals combat damage to an opponent, put a journeyed card you own into your hand.)

Hexproof, crew 6 (Tap any number of creatures you control with total power 6 or greater: This Vehicle becomes an artifact creature until end of turn.)
Whenever The Ark Project deals combat damage to an opponent or planeswalker, gain control of target creature until The Ark Project leaves the battlefield.
Whenever The Ark Project blocks a creature, gain control of that creature.

(Choose only one work as a sorcery to add its ability.)
When The Art of War enters, if a source you control would deal damage this turn, it deals double that damage instead.
{2}{R}{R}: Laying Plans
Whenever you attack for the first time each turn, untap each creature you control. After this phase, there is an additional combat phase.
{2}{R}{R}: Waging War
Whenever a creature you control attacks, create a token that's a copy of it that's tapped and attacking, except the token isn't legendary. Exile those tokens at end of combat.

{T}, Pay 1 life: Add {U}.
{4}{U}{U}{U}, Exile The Aurora's Heart from your hand: Target player draws seven cards.

Creatures you control get +2/+0 until end of turn.

Whenever a creature you control dies, put a unity counter on The Blacksmith's Banner.
Creatures you control have vigilance and get +1/+1 for each unity counter on The Blacksmith's Banner.

[+1]: Remove up to one loyalty counter from each other planeswalker. Up to one target player loses 1 life for each counter removed this way.
[–1]: For each other player and permanent, remove a counter from it or give it another counter of a kind that permanent or player already has.
[–4]: Put target nonland permanent on the bottom of its owner's library.

You draw two cards and you lose 2 life.
Reconstruct {3}{B} (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.)

Until end of turn, target creature you control gains “{T}: Destroy target creature.”

Foretell {1}{B} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)
Return up to two target creature cards from your graveyard to your hand.