msem-instigator

Resolute — Umbral Wolf can't be blocked by more than one creature as long as Umbral Wolf's power is greater than its base power.

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

Unassuming Waif can't be blocked.
Unassuming Waif gets +1/+0 for each other Warrior you control.

Choose one —
• Counter target spell unless its controller pays {2}.
• Tap target creature. It doesn't untap during its controller's next untap step.

You may pay {W} and tap an untapped Monk you control rather than pay this spell's mana cost.
The next 3 damage that would be dealt to you and/or permanents you control this turn is dealt to any target instead.

Encourage ({T}: Another target creature you control gets +1/+1 until end of turn. Encourage only as a sorcery.)
Whenever a creature deals combat damage to a player, if it was encouraged by Unbeholden Navigator this turn, draw a card.

Enchant creature
Enchanted creature can't be blocked.
{1}{G}: Enchanted creature gets +1/+1 and gains hexproof until end of turn.

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

Assault {X}{R}{R} (Whenever this attacks, if it has no +1/+1 counters on it, you may pay its assault cost to put a +1/+1 counter on it.)
Other Elementals you control get +1/+0.
When Unbound Annihilus assaults, create X 1/1 red Elemental creature tokens that are tapped and attacking.

When Unbound Expanse enters the battlefield, if an opponent controls more lands than you, create a Plains token. (It's a basic land with “{T}: Add {W}.”)
{1}{W}, Sacrifice Unbound Expanse: Exile each nonland permanent you control, then return those cards to the battlefield under your control.

Escalate—Return another spell you control to its owner's hand. (Pay this cost for each mode chosen beyond the first.)
Choose one or both —
• Draw a card.
• Draw a card.

Whenever you copy an instant or sorcery spell, you may pay {1}{U}. If you do, draw a card.
Whenever you cast an instant or sorcery spell, you may pay {1}{R}. If you do, Unbound Researchers deals 2 damage to target player or planeswalker.

Whenever you cast another creature spell, create a 1/1 green and white Elk Spirit creature token.
As long as you control five or more Elk, creatures you control get +3/+3 and have trample.

Up to two target creatures each get -3/-0 until end of turn. Tap those creatures. They don't untap during their controller's next untap step.

Target creature gets +1/+0 and gains indestructible until end of turn. Draw a card if you control an Angel, Demon, Faerie or Spirit.

Whenever Unbudging Badger attacks, if its power is 4 or greater, it gains trample until end of turn.

Destroy target artifact or enchantment. You gain life equal to its mana value.

Target opponent sacrifices half the permanents they control, rounded down.

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

Search your library for a permanent card with mana value X or less, reveal it, put it into your hand, then shuffle.

Target creature gets +1/+1 and gains double strike until end of turn. (That creature deals both first-strike and regular combat damage.)

Whenever Uncanny Allocator enters the battlefield or attacks, give any number of permanents and/or players with counters on them another counter of each kind already there.

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

Unceasing Flames deals X damage to any target, where X is 2 plus the number of cards named Unceasing Flames in your graveyard.
Conjure three cards named Unceasing Flames and shuffle them into your main library.

Put two -1/-1 counters on target creature.
Agonize (You may cast this card from your graveyard by putting a -1/-1 counter on a creature you control in addition to paying its other costs. Then exile this card.)