msem-instigator

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

As long as Vinehorn Stag has a +1/+1 counter on it, it can't be blocked by more than one creature.

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.

This spell costs {1} less to cast for each creature that attacked this turn.
Violent Offensive deals 4 damage to any target.

Enchant creature
Whenever enchanted creature becomes tapped, Violent Repercussions deals 3 damage to that creature's controller.

Menace
Whenever a player gains life, that player sacrifices a permanent.

Target creature gains deathtouch until end of turn.
Draw a card.

When Viridian Townships enters, create two Idol tokens. (They're artifacts with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)
{2}, Sacrifice an Idol: Draw a card.
{2}, Sacrifice an Idol: You gain 3 life.

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

Target creature you control deals damage equal to its power to target creature you don't control.

Enchant creature
Enchanted creature blocks each combat if able.
Whenever enchanted creature attacks, it loses flying until end of turn.

{T}: Add {G}.
{T}: Sacrifice Visionary Developer: Create a token that's a copy of target token you control. Activate only as a sorcery.

When Visiting Dignitary enters, gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn.

Vigilance
Whenever Vital Companion attacks, you may put a quest counter on an enchantment you control.

Vitalhydra enters with twice X +1/+1 counters on it.
Each other creature you control enters with a number of additional +1/+1 counters on it equal to the number of +1/+1 counters on Vitalhydra.

When Vitality Reclaimer enters, you may return target permanent card from your graveyard to your hand.

You gain twice X life.
Kindle X—{X}{G}{G} ({X}{G}{G}, Exile this card from your graveyard: Create X 1/1 colorless Elemental creature tokens. Kindle only as a sorcery.)

Eureka! (At the beginning of each end step, you get a research counter if you cast a spell this turn. Then if you have eight or more research counters, remove them and create a Masterpiece token of your choice.)
Equipped creature gets +3/+2.
Equip {R}

Eureka! (At the beginning of each end step, you get a research counter if you cast a spell this turn. Then if you have eight or more research counters, remove them and create a Masterpiece token of your choice.)
Whenever an artifact you control enters, up to two target creatures get +1/+0 and haste until end of turn.

At the beginning of your end step, create an X/X colorless Construct artifact creature token, where X is the number of artifacts that were put into your graveyard from the battlefield this turn.

Vivid Crag enters tapped with two charge counters on it.
{T}: Add {R}.
{T}, Remove a charge counter from Vivid Crag: Add one mana of any color.

Vivid Grove enters tapped with two charge counters on it.
{T}: Add {G}.
{T}, Remove a charge counter from Vivid Grove: Add one mana of any color.

Target creature you control gains trample until end of turn. Whenever that creature deals damage to a player this turn, create a colorless artifact token named Lotus Petal with “{T}, Sacrifice this artifact: Add one mana of any color.”