msem-instigator

Target creature gets +3/+3 and gains trample until end of turn.
Lifecycle {3} ({3}, Discard this card: Create two tapped 1/1 colorless Elemental creature tokens.)

Remove a +1/+1 counter from a creature you control: Regenerate Verendas Brawler. (The next time this creature would be destroyed this turn, it isn't. Instead tap it, remove all damage from it, and remove it from combat.)

Codex — Heraldry; Whimsy; Villainy; Creativity; Brutality. (As this enters, conjure its contents into a shuffled face-up additional library.)
You may spend mana as though it were mana of any color to cast this codex's contents.
Spells you cast are all colors.

Verse of Fire deals 2 damage divided as you choose among up to two targets.

When Vespercloak Vampire dies, create a 1/1 black Bat creature token with flying and lifelink.
Foreshadow {3}{B} (You may cast this spell for its foreshadow cost. If you do, also trigger its “dies” abilities when it enters.)

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.)
Whenever Vessel of Lost Souls envisions a creature card, you may have it become a copy of that card until end of turn.

Whenever a creature attacks you or a planeswalker you control, that creature's controller mills a card.

{2}, {T}, Sacrifice Vial of Dragonfire: It deals 2 damage to target creature.

Return target spell to its owner's hand. If there are three or more colors among permanents you control, you may counter that spell instead.

All creatures get -X/-X until end of turn. X can't be 0.
Whenever a creature dies this turn, create a colorless artifact token named Lotus Petal with “{T}, Sacrifice this artifact: Add one mana of any color.”

When Vicious Shamshir enters, you may attach it to target creature you control. If you do, target creature can't block this turn.
Equipped creature gets +2/+0.
Equip {3}

Choose one —
• Destroy target artifact or enchantment with mana value 3 or less.
• You gain 3 life. Draw a card.

Deathtouch, protection from legendary
Vielle, Undercity Wayfarer has all loyalty abilities of permanents on the battlefield that cost +1, +0, or -1. (Before cost changes. Add or remove loyalty counters from Vielle to pay their loyalty costs.)

Equipped creature gets +1/+3.
Whenever another creature blocks or becomes blocked by equipped creature, that creature loses all abilities until end of turn.
Equip {3}

Vigorbreath Scourge enters with X +1/+1 counters on it.
Whenever Vigorbreath Scourge attacks, it gets +X/+X until end of turn, where X is your devotion to green. Then if its power is 6 or greater, draw a card. (Each {G} in the mana costs of permanents you control counts toward your devotion to green.)

Alpha (You may have this creature enter with a +1/+1 counter on it. If you do, it becomes alpha and can only attack alone.)
Vigilance

Target player sacrifices a creature.
Create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)

When Vile Weavers enters, if you control an enchantment, target player loses 3 life.

When Village Courier enters, look at the top four cards of your library. You may reveal an artifact, enchantment, or land card from among them and put it into your hand. Put the rest on the bottom of your library in any order.

Rhapsody {3}{R}{R} (Pay {3}{R}{R} to cast this as a 4/4, or as a sorcery to make it become a 4/4.)
Whenever Vindictive Guardian or another creature you control enters, if that creature's power is 4 or greater, create a Treasure token.

Whenever Vindictive Pyromancer perseveres, it deals 1 damage to any other target. (A creature perseveres when it survives damage.)

Destroy target nontoken artifact. Create an Idol token. (It's an artifact with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)

As an additional cost to cast this spell, sacrifice an artifact or creature.
Create three 1/1 red Construct creature tokens.

Reverberate {3}{U} (When you cast this spell, copy it if you paid its reverberate cost.)
If Violent Spasm is reverberated, creatures you control gain flying until end of turn. Violent Spasm deals 1 damage to each creature without flying.

{2}, {T}, Sacrifice Virtual Terrain: Search your library for a land card, put it onto the battlefield tapped, then shuffle.