msem-instigator

When Threshing Sundew enters, merge up to one target creature card in your graveyard under it. Threshing Sundew has that card's abilities.
When Threshing Sundew dies, return all other cards merged with it to their owner's hand.

Vigilance, trample
When Threshold Guardian enters, return a creature you control to its owner's hand.

As an additional cost to cast this spell, discard a card.
Draw two cards.

Whenever Tide Crasher attacks, if you control another Merfolk, tap target creature defending player controls.

Permanents you control gain indestructible until end of turn. Untap each creature you control.
Cycling {W} ({W}, Discard this card: Draw a card.)

Experience (Whenever this creature attacks, if it has fewer than three +1/+1 counters on it, put a +1/+1 counter on it.)
When Tidepool Turtle has three or more +1/+1 counters on it, remove them all and transform it.

Nonstoried creatures lose all abilities and have base power and toughness 1/1. (Enchantments and legendary permanents are storied.)

Slipstream (This creature can't be blocked as long as only creatures with slipstream are attacking.)
Crew 1 (Tap any number of creatures you control with total power 1 or greater: This Vehicle becomes an artifact creature until end of turn.)

For each player, you choose from among the permanents that player controls an artifact, a creature, an enchantment, and a planeswalker. Then each player sacrifices all other nonland permanents they control.

For each permanent type, return up to one target card of that type from your graveyard to your hand. (The permanent types are artifact, creature, enchantment, land, and planeswalker.)

Whenever Treasure Hauler attacks, draw a card.
Crew 3 (Tap any number of creatures you control with total power 3 or greater: This Vehicle becomes an artifact creature until end of turn.)

Haste
When Treasure Haulers enters, you may salvage an artifact card. (Exile one from your graveyard until this creature leaves the battlefield. Whenever this creature deals combat damage to a player, put a card it salvaged into your hand.)

As long as you control three or more artifacts, Treasury Master gets +2/+0 and has slipstream. (This creature can't be blocked as long as only creatures with slipstream are attacking.)

When Trenchbottom Mariners enters, you lose 3 life, mill three cards, and create a Treasure token.
Whenever Trenchbottom Mariners attacks, you may cast a permanent card from your graveyard by sacrificing another artifact in addition to paying its costs.

Pressure—{2}{U}{U}, Discard your hand. (You may cast this spell for its pressure cost if seven or more cards are in your graveyard.)
Reveal the top seven cards of your library. Put any number of noncreature, nonland cards from among them into your hand and the rest into your graveyard.

Hexproof
Whenever this creature transforms into Tsunami Titan or attacks, you may return target creature to its owner's hand.

Pressure {5}{G}{G} (You may cast this spell for its pressure cost if seven or more cards are in your graveyard.)
Search your library for three creature cards and reveal them. Put one onto the battlefield, one into your hand, the rest into your graveyard, then shuffle.

{1}{R}, Discard a card: Draw a card.
{R}: You may put a creature card from your hand onto the battlefield. That creature gains haste. Activate only if twenty or more cards are in your graveyard.

Whenever a creature you control dies, Twilight Blade deals 1 damage to each opponent and you gain 1 life.

{1}{U}: Twilight Privateer voyages. (If it isn't blocking or targeted by another spell or ability, it phases out.)
Whenever Twilight Privateer phases in, up to one other target creature voyages.

You may exchange a creature you both own and control with a creature card in your hand that has the same mana value.
Flashback {1}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Slipstream (This creature can't be blocked as long as only creatures with slipstream are attacking.)
{1}{B}, Sacrifice a creature: Put a +1/+1 counter on Twisted Cultist.

You may play Typhoon Caverns from your graveyard as long as seven or more cards are in your graveyard.
Typhoon Caverns enters tapped.
{T}: Add {U} or {B}.
Cycling {1}{U}{B} ({1}{U}{B}, Discard this card: Draw a card.)

{3}{U}: Tap target creature. Activate only as a sorcery.
Cycling {2/U} ({2/U}, Discard this card: Draw a card.)

Haste
Madness {3}{R} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)