msem-instigator

Treacherous Oasis enters the battlefield tapped.
{T}: Add {U} or {B}.
{2}{U}{B}: Until end of turn, Treacherous Oasis becomes a Crocodile creature in addition to its other types. It can't be blocked this turn.
Scavenge {1}{U}{B}

{B}: Treacherous Shade gets +1/+1 until end of turn.
{1}{B}{B}: Treacherous Shade gets +3/+3 until end of turn.

Destroy target creature. Mill a number of cards equal to its power.

When Treacherous Warden enters the battlefield, search your library for a card, put into your graveyard, then shuffle.
Whenever a creature enters the battlefield from your graveyard, each opponent loses 2 life and you gain 2 life.

Target player sacrifices a creature.
Inscribe {3}{B}{R} ({3}{B}{R}: Exile this card from your hand inscribed on a creature you control. Whenever that creature attacks, its controller may cast a copy of the inscribed card without paying its mana cost. Inscribe only as a sorcery.)

(Add a quest counter as this enters. Sacrifice after 3.)
Whenever you scry or search your library, add a quest counter.
1 — Target creature you don't control gets -3/-0 until your next turn.
2 — Reveal cards from the top of your library until you reveal a nonland card, then put the revealed cards into your hand.
3 — Reveal the top card of your library. If its mana value is less than or equal to the number of cards in your hand, you may cast it without paying its mana cost.

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 the battlefield, 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.)

When Treasure Hoard enters the battlefield, create a 2/2 blue Rogue creature token.
{2}{R}, Tap an untapped creature you control, Sacrifice Treasure Hoard: Create two Treasure tokens. (They're artifacts with “{T}, Sacrifice this artifact: Add one mana of any color.”)

Distorted (This creature can be blocked by tapped creatures but not untapped creatures.)
Whenever a Reflection you control becomes the target of a spell, draw a card.

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.)

As Tree of Timelines enters the battlefield, you may pay 3 life. If you don't, it enters the battlefield tapped.
{T}: Add {B}, {G}, or {U}.

{2}{B}, Sacrifice a creature: 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.)
Whenever a +1/+1 counter is put on Treecrawler Elemental, you may have it fight target creature. (Each deals damage equal to its power to the other.)

Flash (You may cast this spell any time you could cast an instant.)
Reach (This creature can block creatures with flying.)

Prevent all combat damage creatures with flying would deal this turn. Creatures you control gain reach until end of turn.

Whenever Tremor Elemental enters the battlefield or you draw a card except during your draw step, Tremor Elemental deals 1 damage to each creature.

Whenever another nontoken creature enters the battlefield under your control, that creature gains haste until end of turn. Then Tremor Seer deals 1 damage to any target.

Whenever Tremor Titan enters the battlefield or attacks, each player sacrifices a permanent. Then you draw a card for each opponent who sacrificed a land this way.

When Trench Breaker enters the battlefield, put target creature on top of its owner's library.

When Trenchbottom Mariners enters the battlefield, 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.

Whenever a land enters the battlefield under your control, put a +1/+1 counter on target creature you control.

Whenever you cast a spell from your graveyard, you may return target nonland permanent to its owner's hand.
Sacrifice a Clue: Return Trespasser of the Gallows from your graveyard to your hand.

This spell costs {1} less to cast for each card you've drawn this turn.
Create three 1/1 white Soldier creature tokens.

Each player sacrifices a creature. (Then exile this card. You may cast the artifact later from exile.)