msem-instigator

Vanguard — Whenever a creature you control attacks alone, it gets +1/+1 and gains menace until end of turn.

Whenever Thundering Towershell attacks, return a creature card with mana value 5 or less from a graveyard to the battlefield under your control. Trigger a death knell of that creature.

Wu Xing (Add effects based on the number of colors of mana spent to cast this spell.)
1 | Attacking creatures get -3/-0 until end of turn.
3 | Thundering Wrath deals 1 damage to each of those creatures.

Flying
Spirited (When this creature enters, you may activate one of its activated abilities without paying its cost.)
{3}{R}{R}, {T}: Exile an instant card with mana value 3 or less from your graveyard, then cast a copy of a card exiled with Thunderlash Mystic without paying its mana cost.

Flash
Whenever Thundermane Fox enters or attacks, target creature you control gains double strike until end of turn.

Flash
Cycling {2} ({2}, Discard this card: Draw a card.)

When Thunderstep Ved enters, it deals 1 damage to any target.

Primal {2}{R}{R} (During your turn, you may cast this spell for {2}{R}{R} instead of playing a land.)
Flying, prowess
At the beginning of your end step, if you didn't cast a spell this turn, sacrifice Thunderstride.

When Thunderwhirl Dancer enters, it gets +X/+X until end of turn, where X is the number of +1/+1 counters among creatures you control. Then it fights up to one target creature.

Creature tokens you control get +1/+1.
Whenever Thyra, Winter's Warden enters or attacks, you may pay {1}{G/W}. If you do, create Bruga, a legendary 2/2 green and white Wolf creature token.

Choose one —
• Draw three cards, then discard a card.
• The owner of target nonland permanent puts it on the top or bottom of their library.

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.)

Choose target creature you control and target creature you don't control. Flip a coin. If the coin comes up heads, put one of those creatures on top of its owner's library. Otherwise, put both of them on top of their owners' libraries.

Each opponent sacrifices a creature or planeswalker.
Acquiesce (If you cast this spell from your hand, exile it as it resolves. When one or more creatures you control deal combat damage to an opponent, you may cast this card from exile without paying its mana cost.)

Vanishing 4 (This creature enters with four time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
Remove a time counter from Tideshift Elemental: You may tap or untap target creature.

Once each turn, when a creature you control becomes tapped, you may untap that creature and tap up to one target creature.

Kicker {X}{U} (You may pay an additional {X}{U} as you cast this spell.)
When Tidetwister Mage enters, if it was kicked, return all other creatures with power X or less to their owners' hands.

Menace, haste
Whenever Tiger of the Drums attacks, choose one —
• Exile target opponent's graveyard.
• You draw a card and lose 1 life.
• Torment each opponent. (They lose 3 life unless they discard a card or sacrifice a nonland permanent.)

Enchant creature
When Til Death enters, exile target creature an opponent controls other than enchanted creature until Til Death leaves the battlefield.
Enchanted creature has defender.

Flying, prowess
Whenever you cast a noncreature spell, reveal the bottom two cards of your library. Target opponent chooses one of them. Put that card on the bottom of your library and the rest into your hand.

Take an extra turn after this one. Exile Time if it wasn't fused.
Fuse (You may cast one or both halves of this card from your hand.)

Instant and sorcery spells you control have leitmotif. (Exile that spell as it resolves if you cast it from your hand. When you next cast a spell that shares a color with that card, you may cast it from exile without paying its mana cost.)

{16}, {T}: Time Cube gains “At the beginning of your end step, if it's not an extra turn, take three extra turns after this one” and loses this ability.

Put target nonland permanent into its owner's library second from the top.