Return target creature card from your graveyard to the battlefield.

Flashback (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Protection from white (This creature can't be blocked, targeted, dealt damage, enchanted, or equipped by anything white.)

Unchained Berserker gets +2/+0 as long as it's attacking.

As Unclaimed Territory enters, choose a creature type.

: Add .

: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type.

Flash (You may cast this spell any time you could cast an instant.)

Enchant creature

Enchanted creature gets +2/+2 and attacks each combat if able.

Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)

When Unctus's Retrofitter enters, up to one target artifact you control becomes an artifact creature with base power and toughness 4/4 for as long as Unctus's Retrofitter remains on the battlefield.

When Undead Butler enters, mill three cards. (Put the top three cards of your library into your graveyard.)

When Undead Butler dies, you may exile it. When you do, return target creature card from your graveyard to your hand.

, : Exile target Skeleton, Vampire, or Zombie.

Manifest dread. (Look at the top two cards of your library. Put one onto the battlefield face down as a 2/2 creature and the other into your graveyard. Turn it face up any time for its mana cost if it's a creature card.)

You may return a permanent card from your graveyard to your hand.

When Undercity Eliminator enters, you may sacrifice an artifact or creature. When you do, exile target creature an opponent controls.

, Sacrifice another creature: Put a +1/+1 counter on Undercity Necrolisk. It gains menace until end of turn. Activate only as a sorcery. (It can't be blocked except by two or more creatures.)

Renown 1 (When this creature deals combat damage to a player, if it isn't renowned, put a +1/+1 counter on it and it becomes renowned.)

: Regenerate Undercity Troll. (The next time this creature would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)

Whenever Undercover Butler attacks the player with the most life or tied for most life, it can't be blocked this turn.

Whenever an artifact you control enters, you may pay . If you do, each opponent loses 1 life and you gain 1 life.

, Sacrifice Underhanded Designs: Destroy target creature. Activate only if you control two or more artifacts.

Constellation — Whenever Underworld Coinsmith or another enchantment you control enters, you gain 1 life.

, Pay 1 life: Each opponent loses 1 life.

Underworld Fires deals 1 damage to each creature and each planeswalker. If a permanent dealt damage this way would die this turn, exile it instead.

Return two target creatures to their owners' hands.

, , Tap an untapped creature you control: Unerring Sling deals damage equal to the tapped creature's power to target attacking or blocking creature with flying.

Menace (This creature can't be blocked except by two or more creatures.)

Whenever Unforgiving One attacks, return target creature card with mana value X or less from your graveyard to the battlefield, where X is the number of modified creatures you control. (Equipment, Auras you control, and counters are modifications.)

Black legendary creatures you control have "bands with other legendary creatures." (Any legendary creatures can attack in a band as long as at least one has "bands with other legendary creatures." Bands are blocked as a group. If at least two legendary creatures you control, one of which has "bands with other legendary creatures," are blocking or being blocked by the same creature, you divide that creature's combat damage, not its controller, among any of the creatures it's being blocked by or is blocking.)

Converge — Create a 1/1 white Kor Ally creature token for each color of mana spent to cast this spell.

Unimpeded Trespasser can't be blocked.

Support 2. (Put a +1/+1 counter on each of up to two target creatures.)

Untap each creature you control with a +1/+1 counter on it.

Destroy target creature. If you control an artifact, Unlicensed Disintegration deals 3 damage to that creature's controller.

When Unlucky Witness dies, exile the top two cards of your library. Until your next end step, you may play one of those cards.

Return target permanent card from your graveyard to your hand. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Return up to one target nonland permanent to its owner's hand. Manifest dread. (Look at the top two cards of your library. Put one onto the battlefield face down as a 2/2 creature and the other into your graveyard. Turn it face up any time for its mana cost if it's a creature card.)

Choose target artifact or enchantment. Its owner shuffles it into their library.

When Unscrupulous Contractor enters, you may sacrifice a creature. When you do, target player draws two cards and loses 2 life.

Plot (You may pay and exile this card from your hand. Cast it as a sorcery on a later turn without paying its mana cost. Plot only as a sorcery.)

Pay 3 life: Put a +1/+1 counter on target creature.

Kicker (You may pay an additional as you cast this spell.)

Damage can't be prevented this turn. If this spell was kicked, it deals 5 damage to target player or planeswalker.

Enchant creature

Enchanted creature gets +3/+3.

At the beginning of the upkeep of enchanted creature's controller, put a -1/-1 counter on that creature.

Return target spell or creature to its owner's hand.

Trample

Other Wolves and Werewolves you control have trample.

: Put a +1/+1 counter on target creature.

Nightbound (If a player casts at least two spells during their own turn, it becomes day next turn.)

Trample

Whenever Untethered Express attacks, put a +1/+1 counter on it.

Crew 1 (Tap any number of creatures you control with total power 1 or more: This Vehicle becomes an artifact creature until end of turn.)

Destroy target creature. Its controller manifests dread. (That player looks at the top two cards of their library, then puts one onto the battlefield face down as a 2/2 creature and the other into their graveyard. If it's a creature card, it can be turned face up any time for its mana cost.)

Vigilance

Eerie — Whenever an enchantment you control enters and whenever you fully unlock a Room, put a possession counter on Unwilling Vessel.

When Unwilling Vessel dies, create an X/X blue Spirit creature token with flying, where X is the number of counters on Unwilling Vessel.

Flying

Sacrifice Unyaro Griffin: Counter target red instant or sorcery spell.

Target creature gains flying until end of turn.

Draw a card at the beginning of the next turn's upkeep.

Upriser Renegade gets +2/+0 for each other modified creature you control. (Equipment, Auras you control, and counters are modifications.)

Draw three cards. You may play an additional land this turn.

: Add .

: Target creature loses first strike or swampwalk until end of turn.

Kicker (You may pay an additional as you cast this spell.)

When Urborg Emissary enters, if it was kicked, return target permanent to its owner's hand.

Urborg Volcano enters tapped.

: Add or .

: Add .

Ursine Fylgja enters with four healing counters on it.

Remove a healing counter from Ursine Fylgja: Prevent the next 1 damage that would be dealt to Ursine Fylgja this turn.

: Put a healing counter on Ursine Fylgja.

If a source would deal damage to you, prevent 1 of that damage.

: Add .

, , Sacrifice Urza's Cave: Search your library for a land card, put it onto the battlefield tapped, then shuffle.

Trample

: Urza's Engine gains banding until end of turn. (Any creatures with banding, and up to one without, can attack in a band. Bands are blocked as a group. If any creatures with banding you control are blocking or being blocked by a creature, you divide that creature's combat damage, not its controller, among any of the creatures it's being blocked by or is blocking.)

: Attacking creatures banded with Urza's Engine gain trample until end of turn.

, Discard a card: Search your library for a card that shares a complete word in its name with the discarded card, reveal it, put it into your hand, then shuffle.

: Add . If you control an Urza's Mine and an Urza's Tower, add instead.