msem-instigator

Flash
When Veilborn Meddler enters, counter target spell if its mana value is less than or equal to Veilborn Meddler's power.
Whenever you cast a spell during an opponent's turn, put a +1/+1 counter on Veilborn Meddler.

Menace
Whenever another creature dies, put a +1/+1 counter on Veilborn Stalker.

Haste
Whenever you cast a noncreature spell, put a +1/+1 counter on Vengeant Precursor. It gains trample until end of turn.

Flash
Flying
Sacrifice Vengeful Messenger: Counter target noncreature spell unless its controller pays {2}.

Trample
Whenever a creature dies, put a +1/+1 counter on Venomclaw Skitterer. You gain 1 life.

Enchant land
When Verdant Haven enters, you gain 2 life.
Whenever enchanted land is tapped for mana, its controller adds an additional one mana of any color.

[+1]: Each player discards a card or sacrifices a creature.
[–3]: Vikalden deals X damage to any target and you gain X life, where X is the number of Swamps you control.
[–5]: You get an emblem with “{B}, Pay 2 life: Draw a card.”

Whenever one or more creatures die for the first time each turn, you draw a card and you lose 1 life.
Whenever you cast a black noncreature spell, Villainy deals 2 damage to any target and you gain 2 life.

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.

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.

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 Creek enters tapped with two charge counters on it.
{T}: Add {U}.
{T}, Remove a charge counter from Vivid Creek: 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.

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

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

Crystallize. (Put a +1/+1 counter on a creature you control or create a Treasure.)
Voice of the Universe deals 2 damage to each creature.

{5}, {T}, Sacrifice Voidlife Orbs: Destroy all nonland permanents. You can't spend more than one color of mana to activate this ability.

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.)
[+1]: Untap up to one target artifact you control.
[–2]: Draw three cards. Then discard two cards unless you discard an artifact card.

WZ-18 Troublemaker enters with a +1/+1 counter on it.
When WZ-18 Troublemaker dies, put its counters on target creature you control.
{1}{R}, Exile WZ-18 Troublemaker from your graveyard: It deals 2 damage to each opponent.

Wandering Megaflora has hexproof as long as it's untapped.
Whenever Wandering Megaflora attacks, untap another target creature you control.

Whenever you cast a spell, Wandering Precursor gets +1/+0 until end of turn for each color of mana spent to cast that spell.

Create X 1/1 white Spirit creature tokens with flying, where X is two plus the number of cards named Wandering Souls in your graveyard. Conjure three cards named Wandering Souls and shuffle them into your main library.

When Wandering Visionary enters, draw a card.
{W}{U}{B}{R}{G}: Create a 1/1 blue Elemental creature token with flying.

Augmented — When you cast Want It All, if you've spent {W}{U}{B}{R}{G} to cast spells this turn, copy Want It All for each other spell cast this turn.
Shuffle your library. Then exile the top card of your library. You may play it without paying its mana cost.