msem-instigator

When Ulek Elder enters, look at the top card of your library. You may put it into your graveyard.

Vision (Whenever this or another creature you control enters, reveal the top card of your library. Then you may put that card into your graveyard.)
As Ulek Wayfinder envisions a land card, you may put that card onto the battlefield tapped.

When Ulvenwald Ranger enters, surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)
{1}{G}: Transform Ulvenwald Ranger. Activate only if it's attacking.

If a creature card would be put into an opponent's graveyard from anywhere, instead exile it, then copy it. You may cast the copy. (You still pay its costs, including color. Copies of permanents enter as tokens.)

Flash
If a card or token would be put into an opponent's graveyard from anywhere, exile it instead.

Whenever a Wizard you control deals damage to a player, draw a card.

Unbound Spirit can't be blocked.
When you attain Unbound Spirit, tap target creature. That creature doesn't untap during its controller's next untap step.

When Unburdening Priest enters, you may exile any number of creatures you control not named Unburdening Priest, then return those cards to the battlefield under your control.

Spend only mana produced by Treasures to cast spells.
{2}, Discard a card: Create two Treasure tokens.

Slipstream (This creature can't be blocked as long as only creatures with slipstream are attacking.)

Flash
If an opponent would draw a card, that player exiles the top card of their library instead. During each player's turn, that player may play that card for as long as it remains exiled.

Bleed {1}{B} (You may cast this spell for its bleed cost if an opponent lost life this turn.)
When Undermurk Scavenger enters, you draw a card and you lose 1 life.

Vigilance
Whenever Underpass Sentinel enters or attacks, you may put a +1/+1 counter on another target creature you control without one.
Sacrifice Underpass Sentinel: Embattled creatures you control gain hexproof and indestructible until end of turn. (A creature is embattled if it has a counter on it or a permanent you control attached to it.)

At the beginning of your upkeep, reveal the top card of your library. If it has the same name as a card in your graveyard, put the revealed card into your hand. Otherwise, put it into your graveyard.

Zombiecycling {1}{B} ({1}{B}, Discard this card: Search your library for a Zombie card, reveal it, and put it into your hand, then shuffle.)
Unearth {1}{B} ({1}{B}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the end step or if it would leave the battlefield. Unearth only as a sorcery.)

Ungoverned Sneak can't be blocked by creatures with greater power.
Attain {3}{U} ({3}{U}: Transform this. Spend at least three colors of mana to activate this, and only as a sorcery.)

Cadence (Whenever you cast a spell, if its mana value is greater than this creature's power, put a +1/+1 counter on this creature.)
United Patrol can block an additional creature each combat.

When Unmasker of Fate's Design enters, look at target player's hand. Choose a nonland card from it and exile that card with a puzzle counter on it. As long as that card has a puzzle counter on it, that player may pay {2} and 1 life at any time. If they do, return the exiled card to their hand.

Menace
Foresight — Whenever you draw your second card each turn, target player loses 2 life and you gain 2 life.

Trample
Defiance (Whenever this creature takes damage, if it survives and wasn't defiant, put a +1/+1 counter on it and it becomes defiant.)

Trample, ward {1}
Whenever you gain life, put a +1/+1 counter on Unrelenting Noble.
{1}, Sacrifice a permanent: You gain 2 life.

This spell costs {2} less to cast if your starting deck contained at least forty cards more than the minimum deck size.
When Unrivaled Fireweaver enters, you may exile a red instant or sorcery card you own from outside the game. Until the end of your next turn, you may play that card.

Prowess
Whenever Unseen Hand attacks, exile target noncreature, nonland card with mana value 1 or less from your graveyard. Copy that card. You may cast the copy. (You still pay its costs.)

Glitch—Sacrifice a creature. (Remove one [restriction] for each time you pay the glitch cost.)
When Unshackled Revolutionary enters, you may destroy target creature an opponent controls [with mana value 3 or less]. [You lose 3 life.]

Experience (Whenever this creature attacks, if it has fewer than three +1/+1 counters on it, put a +1/+1 counter on it.)
Unstoppable Weed gets +1/+1 for each +1/+1 counter on other creatures you control.