msem-instigator

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 the battlefield, 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.

Discard a card: Unseen Maniac gets +1/+1 and can't be blocked this turn.
Whenever Unseen Maniac deals combat damage to a player, draw a card.

You may have Unstable Impersonator enter the battlefield as a copy of any creature on the battlefield chosen at random.

Vanishing 5 (This permanent enters the battlefield with five time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
{1}{R}, Remove a time counter from Unstable Magmaling: Flip a coin. If you win the flip, it deals 3 damage to any target.

Unstoppable Slaughter deals 1 damage to each creature and each player. Whenever a creature dealt damage by Unstoppable Slaughter this turn dies this turn, repeat that process.

Choose one, then choose another for each card named Unsuspecting in your graveyard.
• You may return a permanent you control to its owner's hand.
• You may put an artifact, creature, or land card with mana value 2 or less from your hand onto the battlefield.
• Untap up to three target permanents.
• You gain 4 life.

Whenever a land becomes tapped, its controller sacrifices it and creates a Treasure token.

Whenever you cast a nongreen spell, creatures you control get +1/+1 until end of turn.
Wanderlust — When Untethered Disciple enters the battlefield, if you control four or more differently named lands, create two 1/1 Scout creature tokens that are all colors.

For each land you control, you may return a land card from your graveyard to the battlefield tapped.

Untrekked Territory enters the battlefield tapped.
{T}: Add {B} or {G}.
When Untrekked Territory enters the battlefield, you may put a loyalty counter on a planeswalker you control.

When Unwavering Sentinel enters the battlefield, for each creature you control, create a white Aura enchantment token named Shield with “Enchant creature” and “If enchanted creature would be destroyed, instead remove all damage from it and sacrifice this Aura” attached to that creature.

Ward {1}
Other Scouts you control get +1/+1.
Whenever three or more Scouts you control attack, draw a card.

Unzari Ruins enters the battlefield tapped.
{T}: Add {C}.
Tap five untapped creatures you control: Unzari Ruins becomes a 10/10 Construct artifact creature with trample until end of turn. It's still a land.

Constructs you control have haste.
When Urak, Voice of the Horde or another Construct enters the battlefield under your control, creatures you control get +1/+0 until end of turn.
Respawn (When this creature dies, if it attacked this turn, return it to its owner's hand.)

When Urn of Heroes enters the battlefield, you may search your library for a legendary card, put that card into your graveyard, then shuffle.
{T}: Add {C}.

You may have Urushi, the Ripple in the Smoke enter the battlefield as a copy of any creature on the battlefield, except it's an enchantment. (It's not a creature.)

Golden age (If you cast an instant or sorcery spell, activated a nonmana ability, and attacked this turn, enter a renaissance for this game.)
When Ushi Yun enters the battlefield, create an Idol token.
As long as you're in a renaissance, artifacts you control have “{T}: Draw a card.”

Foretell {B} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)
Destroy target creature or planeswalker. You lose 4 life unless this spell was foretold.

Foretell {X}{U} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)
Gain control of target creature with power 2 or less. If this spell was foretold, gain control of target creature with power X or less instead.

Deception {1}{B} ({1}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Unblocked attacking creatures you control get +1/+0.

Melee (Whenever this creature attacks, it gets +1/+1 until end of turn for each opponent you attacked this combat.)
When Vaeldan's Liberator dies, you may exile it. If you do, return a permanent card with mana value less than or equal to Vaeldan's Liberator's power from your graveyard to your hand.

As long as an opponent has one or fewer cards in hand, Valdez gets +2/+0 and has menace.

First mate—There are four or fewer different mana costs among nonland cards in your starting deck. (If this card outside the game is your chosen first mate, you may swap it with a card in your opening hand.)
First strike
Each spell your opponents cast that would cost less than three mana to cast costs {1} more to cast.

Advance {6}{W}{W} (Cast this for {6}{W}{W} to advance it as it enters. {6}{W}{W}: Advance this as a sorcery.)
Flying, vigilance, lifelink
Whenever Valera, Constructed Angel advances, destroy all nonartifact creatures.

Vigilance
Engage (This creature must be blocked each combat if able.)
Other Soldiers you control get +1/+1 and have first strike.